Australian insects

Among the introduced species common in Australia is the Cabbage Aphis, Aphis brassicae, a dull green insect covered with a floury exudation; it is one of the greatest pests that the cabbage-growers have to deal with, and is always most troublesome in dry weather. The Rose Aphis, Siphonophora rosae, is a pale green species appearing in the spring on the young buds of the roses, but seldom doing very serious damage. The Woolly Aphis, Schizoneura lanigera, common both on the roots and branches of apple trees, is found in most of our old orchards; the dull blue aphids cluster together in colonies with their beaks buried deeply in the bark, and the clusters become covered with a mass of soft white flocculent exudation, hiding them from view. From the irritation to the plant tissue caused by their presence large galls or excrescences appear all over the branches. The Peach Aphis, A. persicae-niger, is another common orchard pest which winters on the roots of the peach trees: in early summer they commence to spread, and if neglected do a great deal of damage to the leaf and flower buds.

The chief work dealing with the systematic classification of plant lice is Buckton’s “Monograph of the British Aphidae,” published by the Roy. Society, London 1881. A number of new species have been described since by American entomologists in bulletins on Economic Zoology.

Family 8. Snow-Flies.
ALEURODIDAE.

These are all very small delicate creatures; both sexes are furnished with two pairs of broad rounded wings with simple parallel veins, and are usually thickly covered with a mealy white dust from which they take their popular name of “Snow-Flies.” The head is broad, furnished with a three-jointed beak enclosing setae; seven-jointed antennae; and large reniform eyes, with an ocellus on either side above the eyes. The thorax is broad and the abdomen soft and rounded. The tarsi are two-jointed terminating in two claws at the extremities.

The female lays her eggs in clusters on the under surface of the leaves, where the young larvae later on form regular oval, glassy tests of various colours, enclosed in which they feed and finally pupate. The adult insects have their short broad wings slightly expanded, and cluster together in threes and fours: but the moment their food plant is touched they fly out in a little cloud. They can, like the scale insects, be very easily introduced into a new country with their food plant, and several species, like Aleurodes vaporariorum described by Westwood from Europe, have a wide range over America and this continent.

The snow-flies are well represented in Australia, and several species do a considerable amount of damage to native shrubs, but on account of their delicate structure and small size they are difficult to collect, and harder to preserve when collected; if mounted on card they dry up, with nothing to determine them from but the wings, which have very few distinctive characters. The most satisfactory method of preserving them, is to drop the live insects into oil of cloves on a micro slip, when they usually open their wings and legs, and then make, with a little care, very fine objects when mounted in balsam; at times, however, the floury covering floats off the wings and body and sometimes clouds the mount.

Maskell has described 8 species from Australia (Trans. N. Zealand Inst. 1896); most of these descriptions, however, were based upon the larval tests or scales (and not the adult insects) which had been sent to him under the idea that they were scale insects; so that whoever takes up the study of snow-flies will have to breed them out, to be sure of the identity of his species. Aleurodes styphelia forms a flattened, oval, black test fringed with white waxy tubes almost as long as the encircled larva, scattered about over the leaves of Styphelia richei, a common scrub bush about Sydney. Aleurodes t-signata forms a spiny black test; and with a second undetermined pale yellow species without a marginal fringe, is found about Sydney on the foliage of Acacia longifolia. Another species, A. banksiae, is found upon both the honeysuckle (Banksia) and the bottle brush (Callistemon).

In Maskell’s paper, which is an important contribution to the study of these small but very interesting insects, he lists 65 known species belonging to the typical Genus Aleurodes; some have since been described from America, of which a few have been placed in the Genus Aleurodicus, formed by Douglas for those with a distal and basal branch on both wings.

Family 9. Scale Insects.
COCCIDAE.

These insects take their popular name of scale insects from the habit that many of the typical species have of protecting themselves, after they have settled down on their food plant, by forming a shield or scale over their backs under which they feed and produce their eggs or living larvae. To form the scale the moulted larval skin, called the pellicle, becomes a nucleus in the first place, round which exudations are added until the scale insect ceases growing.

The larvae are pale yellow, pink, or dull-red coloured little creatures, oval or shield-shape in form, usually fringed round the margins of the body with fine filaments, which are often long upon the somewhat thickened irregularly-jointed antennae and form longer setae upon the tip of the abdomen. They have distinct black eyes, well-developed legs; the mouth is pointed and beak-like. At this stage of their existence the sexes do not differ in outward appearance, but when they attach themselves to their food plant the males and females of the same species often construct scales of very dissimilar form; while in others the male scales are simply more elongate than those of the female.

The male coccid is a delicate fragile little creature, usually microscopic in size, so that, unless bred out in confinement from scale-infested foliage, they are seldom seen. He has a well defined head rounded behind, furnished with moderately long antennae composed of thickened irregularly-jointed segments fringed and surmounted with fine filaments. The globular black eyes stand out on the sides of the head, but the mouth is aborted so that it cannot feed. The thorax, lobed on the dorsal surface, is furnished with a pair of rounded wings each with a simple central nervure, but he can fly well in spite of their delicate structure. The slender legs are simple, terminating in rudimentary hooks; the elongated abdomen is distinctly segmented and furnished at the extremity with a pair of long slender white filaments. This period of his existence is short: thousands of them perish very soon after they leave their scale, and the survivors as soon as they have impregnated the female die.

The female coccid as soon as she settles down to suck up the sap develops under her protective shield (which, unlike the male, she never leaves) into an oval or rounded yellow mass: her legs, antennae, and even head become aborted though the segments of the abdomen are well defined in most species, and finally she becomes simply a sack of eggs. She deposits her eggs under the protection of the shield, in other cases the larvae develop within her shrunken dead skin.

The larvae swarm out and spread over plants when, owing to their immense numbers sucking up the sap with their sharp beaks, they soon injure the tissue and often kill the food plant. Thus from an economic point of view the scale insects are one of the most important groups of the insect-world that man has to deal with, and thousands of pounds are spent in spraying and fumigating cultivated trees to destroy these pests. Many species are cosmopolitan in their range and choice of food plants, having been introduced all over the world, but Australia has a great number of indigenous species, many remarkable for their curious habits, particularly those forming solid woody galls on the eucalypts.

The classification of the scale insects is based chiefly upon the structure of the adult female coccid, viz.:—Of the spinnerets, abdominal cleft, lobes, spines, and anal ring of the abdomen, and the structure and number of joints of the antennae. The shape and structure of the puparium or scale, or other secretions are used to separate them into the larger sub-divisions.

The greater number of our species were described by Maskell in the “Transactions of the New Zealand Institute between the years 1878–1898,” in which period he added over 100 new species to our list: Green (Pro. Linn. Soc. N.S.W. 1900) has described some others; and in the same Journal (1882–1898) I dealt with the gall-making coccids belonging to the sub-family Brachyscelinae. In 1894 Maskell issued a “Synoptical List of the Coccidae reported from Australia and the Pacific Islands,” in which 180 species were credited to Australia. To this Maskell added later a number of new forms; and Fuller others from Western Australia (Trans. Ent. Soc. London 1899). In Mrs. Fernald’s “Catalogue of the Coccidae of the World” (Hatch Experiment Station Bulletin 88, 1903) over 328 species are listed, from this country, but there are a considerable number of doubtful species among them.

The Coccidae have been divided into a number of sub-families: I follow Green (Coccidae of Ceylon, 1896), though Mrs. Fernald in following Cockerell reverses the families and starts with the mealy bugs; I also retain most of the well-known generic names unless there is a very valid reason for discarding them, which does not appear to be the case in many of Cockerell’s amendments.

The Sub-family Diaspinae are known as armoured scales and embrace most of the forms which cover themselves with stout horny shields (puparia). When adult the female is almost legless, with rudimentary antennae, and incapable of movement. The members of the Genus Aspidiotus form round scales, and among them are some of our worst orchard pests. The introduced species Aspidiotus auranti, the Red scale of citrus trees, is now found on many garden shrubs. The puparium of the adult female is dull reddish yellow with the centre lighter coloured, and the twigs, leaves and fruit of neglected trees are often covered with these scales in all stages of growth. A. perniciosus, the notorious San José Scale, that attacks deciduous fruit-trees in the same manner, is a dull brown circular scale; its original home is somewhat doubtful, and though it was first recorded as a pest in California, is said to have come from China. The scales are much darker than those of the red scale, and infest the branches and twigs so thickly that they destroy the bark, and whenever they attach themselves to the fruit produce a red spot. A. hederi (better known under the name of A. nerii), is a pure white scale with a yellow centre; it has a world-wide range, and its range extends far out into our western scrubs, sometimes covering the whole of a large tree. A. rossi is a very distinct, round, black scale, partial to Euonymus in the garden, and to grass trees in the bush. A. ficus is often known as the “Round Scale” from its size and regular shape; it is deep chocolate brown in colour, common upon palms, and is sometimes found upon oranges coming from the Pacific Islands.

Fiorinia acaciae covers the stems and twigs of Acacia longifolia with its narrow white ribbed scale; it is much longer than broad, and is truncate at the extremities; this gives it a very distinctive character.

The Genus Diaspis contains a number of delicate, more elongated scales, among which is the well known white rose scale Diaspis rosae, common in the garden. Poliaspis exocarpi is another white scale infesting Oxylobium, Dillwynia, and other bush shrubs; the male scales are long, slender, and loosely attached to the smaller twigs.

The Genus Chionaspis, containing a number of cosmopolitan and indigenous species, has the base of the scale narrow, elongate, but broadly rounded at the extremity. Chionaspis xerotides is white, common upon the blades of the sedge growing along the sea shore at Botany, N.S.W., and has a wide range. C. eugeniae is a larger broader scale, variable in size and shape; it infests several native shrubs, and a very large form is found on the waratah.

Mytilaspis is another world-wide genus, in which the scales are attenuated at the base and are oyster-like in shape; Mytilaspis pomorum is the common “Mussel” or “Oyster” scale of the apple tree found all over the world. M. spinifera is a handsome, broad, white scale common on the weeping myall (Acacia pendula), growing in the interior. M. striata is a very slender form of scale that has had to adapt its shape to the slender foliage of the Casuarina which it infests. M. acaciae is a grey species that clusters thickly together in masses like the apple scale, covering the stems of several different species of Acacias in the bush with its stout irregular scales.

Plate XXXIV.—HOMOPTERA.

Family Coccidae.

In the Sub-family Lecaniinae the female coccids are active or stationary; naked or covered with some secretion; sometimes without legs; the abdomen marked with a median cleft and furnished with two dorsal lobes. Several species of the tropical Genus Ceroplastes are found about Sydney, where they were introduced into the gardens at a very early date, and have since spread into the orchards and bush. The Indian wax-scale, Ceroplastes ceriferus, covers orchard trees, and bush and garden shrubs with its irregular rounded masses of greasy white matter that protect the liver-coloured coccids beneath. C. rubens is a smaller and more regularly rounded dull red scale, the enveloping material forming a hard waxy shell.

The members of the Genus Ctenochiton are chiefly confined to New Zealand, but two fine species have been described from Australia. Ctenochiton eucalypti comes from the Newcastle district, N.S.W., where it infests the leaves of gum saplings. The scales of the sexes differ very much; those of the male are slender, white, and glassy, while those of the female are broad and dark coloured. C. rhizophorae comes from Queensland, where it is found upon the mangrove. The beautiful, brittle, glass-like scales of Inglisia foraminifer and I. fossilis, are often very plentiful in the interior on low scrub trees.

In the Genus Ceronema, the males form delicate angulated scales, but the females are clothed with a woolly secretion. Ceronema banksiae is a somewhat rare scale found on the foliage of the banksia; it has the secretion upon the dorsal surface, formed into a distinct rib down the centre. C. caudata is a large species with a white woolly covering, a large filament towards the apex forming a large loop rising above the back like a handle. It has a wide range from the South Coast of N.S.W. to North Queensland, and about Bulli, N.S.W., is found on gum trees.

The Genus Lecanium (which has been cut up into a number of new genera) contains many distinct species peculiar to our fauna. Lecanium tesselatum, a flattened species with crenulated margins, and common on palms in the gardens, and L. oleae, known as “black bug” or “olive scale” by the orchardists, are both introduced species: L. patersoni is a slender form found upon the foliage of Patersonia glabrata growing about Sydney. L. scrobiculata is a bright, shining, convex, dark brown scale infesting several species of acacias; and L. mirificum, one of the largest, is found in the interior upon Acacia pendula. The curious coccid, Cryptes (Lecanium) baccatum, covers the twigs of several acacias, among them the common black wattle in the vicinity of Sydney. At first dull white, they swell out into rounded bead-shaped, blue sacks, so close together that they encrust the whole of the infested twig; when adult they turn dull brown.

The Sub-family Dactylopinae contains most of the well-known “mealy bugs”; they are soft bodied creatures in the earlier stages of their existence, and many species are able to move about until their latter days; instead of forming a separate scale like the first group, they cover themselves with white, woolly, mealy, cottony, or waxy secretions.

The members of the Genus Asterolecanium are represented in Australia by the introduced “oak scale” Asterolecanium quercicola, a typical form which, half buried in the infested bark at the tips of the branches, is covered with a waxy, greenish yellow, rounded scale; when numerous it causes the tips of the branches to die back. A. acaciae, when numerous, aborts the bark and twigs of Acacia longifolia and is covered with dull brown and white shields; and with A. stypheliae, with its raised, shining, oval, bright yellow tests, found on a number of different shrubs, are both native species with a very wide range over Australia.

The Genus Rhizococcus is represented by 8 species, found chiefly upon the twigs of wattles (Acacia) and she-oaks (Casuarina); and the cosmopolitan Genus Eriococcus by 17 species. Several species of Eriococcus enclosed in their egg-shaped, white-felted sacks are very common in the forest, clustering over and often killing the young trees. Eriococcus coriaceous varies from white to yellow in colour; the sacs are oval, with a distinct anal opening on the summit; they infest the foliage and twigs of many young Eucalypts. E. paradoxus is a somewhat larger, sticky insect; they mass together in regular lumps on the twigs of the same trees: while E. eucalypti, as far as my experience goes, is never found on gum trees, as its name implies, but upon the prickly twigs of Bursaria spinosa, and its sacs are more depressed and have a browner tint.

The typical Dactylopius are free-moving insects, often crawling about until their final stage, when they become covered or surrounded with flocculent woolly matter. Dactylopius albizziae is common on the black wattle, and is sometimes a pest in wattle plantations; it is a blackish-blue berry-shaped coccid surrounded with and lightly clothed on portions of the dorsal surface with white mealy and woolly filaments. D. aurilanatus is chiefly confined to the branchlets of Araucaria bidwilli, or “Bunya Bunya.” It is very abundant at times on these trees in the Sydney gardens, and is easily recognised by the broad lines of sulphur-yellow meal or down across the dorsal surface. D. lobulatus is an oval coccid, hiding under loose bark on the trunks of the blue gum, Eucalyptus globulus; it is so thickly clothed with white mealy secretion forming filaments round the edges that its form and colour are quite hidden.

In the Genus Ripersia the species have a world-wide range; they are curious wrinkled naked coccids, but are sometimes more or less enveloped in a white covering; they lead an underground existence on the roots of grass and plants: a single species is recorded by Maskell from S. Australia on the roots of a Leptospermum. The curious Antonina australis is an underground coccid which infests the roots of the Nut-grass, Cyperus rotundus, and was described by Green (Pro. Linn. Soc. N.S.W. 1904) from specimens obtained in the Hunter River district, N.S.W., where it was so plentiful that in the dry seasons it killed a great deal of this sedge. The adult female is a rounded black smooth shining creature about ⅛ of an inch in diameter, enveloped in a coat of white woolly secretion, from which it can be easily removed. The legs and antennae are aborted, but the segmental divisions of the abdomen remain, and the tip is produced into two irregular roughened tubercles, joined at the base with a tuft of stout bristle-like hairs.

Plate XXXVI.—HOMOPTERA.

Family Coccidae.

The Sub-family Tachardiinae contains a number of remarkable species, some of considerable commercial value on account of the resinous secretion they encrust themselves with; this secretion is known as lac, and is used for making varnish. The typical female is an irregular wrinkled fleshy mass with a pair of tubular appendages on the back. These appendages were supposed at one time to be used for producing the lac, but Green considers them to be breathing structures. Five species are described from Australia, of which Tachardia australis is so thickly encrusted with reddish brown lac, that it might be of some commercial value in the future; it is very plentiful upon Melaleuca bushes near Maryborough, Queensland, but was described by me from specimens obtained on a small shrub, Beyeria viscosa, at Gunnedah, N.S.W. T. decorella is enclosed in a very dainty, flattened, ribbed, cushion-like mass of dull slate-coloured lac; it is found on a number of different trees, among them the water gums (Eugenia smithii); and I have also found it on the desert cypress (Callitris) in the interior.

The Sub-family Idiococciinae comprises a number of very curious coccids, some of which are naked; some form waxy tests; while others are enveloped in woody galls. Maskell, who created this division, says they are separated from the Monophlebiinae by the absence of anal tubercles and the antennae, and from the Brachysceliinae by the absence of anal appendages. The members of the Genus Sphaerococcus number 21 described species, all but two of which are peculiar to Australia; some form galls, others waxy tests. Sphaerococcus pirogallus cover the whole of the tips of the bushes of Leptospermum flavescens with its curious little pear-shaped galls. At first pink or red, these galls are dull brown when full grown, and have an aperture on the side of the stalk, and the coccid within is attached to a saucer-like rim on the roof of the apex. This is one of the commonest galls about Sydney; acres of these low bushes often have the whole of their foliage covered with masses of these small galls. S. melaleucae does not form a gall, but surrounds itself with a dark waxy secretion like the lac insect; both scales and twigs are often blackened with smut or fumagine. L. leptospermi forms a swelling in the twig which looks as if the tissue had risen over it like a blister and then split down the middle, exposing the dorsal surface. S. froggatti is very common on the tips of Melaleuca bushes growing about Sydney; the dull red coccid is clothed with white secretion resting in an excrescence fringed with slender, reddish brown finger-like processes curling over in an irregular protective gall. S. socialis produces a very curious greyish globular gall with no opening on the outside, and measures up to ½ an inch in diameter. Maskell says: “The outer surface is formed of very closely imbracted scales, which are apparently aborted and coalesced leaves of the tree”; the interior is of a loose structure containing several female coccids, and a few males. It was collected by Lea near Geraldton, W. Australia.

The Genus Cylindrococcus contains 3 species which form curious cone-like galls upon the twigs of the She-oak, Casuarina. Cylindrococcus spiniferus varies much in size and shape. They are often very numerous, covering the whole of the bush with their curious, rough, bracteate galls, which are rounded at the base and taper to the extremity. The female, a cylindrical, dull red creature, is enclosed in an elongate, thin tube, which occupies the centre of the gall; this tube is attached at the base of the gall and is surrounded with the bracts. Some of the typical forms might be easily mistaken for seed cones. C. amplior, which is a more solitary species, forms a solid seed-shaped gall with the base set in a bract like the calyx of a flower, and the whole might be likened to an unopened bud. It is found in South Australia and the north-western parts of Victoria.

Plate XXXV.—HOMOPTERA.

Family Coccidae.

The Sub-family Brachysceliinae contains some of the most remarkable insects in our fauna. They were first noticed by Schrader (Trans. Ent. Soc. N.S.W. 1862), who described and figured a number of our commonest species and their galls; to these I have added a number of new species (Pro. Linn. Soc. N.S.W. 1892–1898). They are all gall makers; the beautiful little larva born in the gall is usually yellow, oval, flattened, and fringed round the margin with short glassy filaments. In most species the full-grown female has antennae and legs aborted, and becomes simply a sac of eggs and liquid matter enclosed in a leathery skin, and is furnished with horny tail appendages.

The Genus Frenchia was formed by Maskell for a species, Frenchia casuarinae, which forms a gall like a stout blunt thorn; it is about the thickness of a slate pencil and has a small opening at the apex. These twig-like galls spring directly from the branch of the infested Casuarina, while the aborted tissue at the base swells out like a blister. The slender, attenuated, red female coccid rests head downward with the tail reaching up to the apical orifice of the gall. A second species, F. semiocculta, forms a raised swelling on the twigs of Casuarina, with a cleft in the centre, thus forming two lobes. The first is common in Tasmania, Victoria, and N.S. Wales; the latter was collected at Manly, near Sydney.

Schrader called the next Genus Brachyscelis, but Rubasmann finding the name preoccupied changed it to Apiomorpha; over 30 species are given in Mrs. Fernald’s Catalogue, but there are several species described both by Rubasmann and Tepper that were described from variable or aborted galls that may prove to be synonyms. The female is remarkable for forming a stout woody gall, sometimes sessile, sometimes springing from a stalk; it encloses an oval cell with a circular or transverse aperture at the apex of the gall, through which the male impregnates her by means of his long slender abdomen. The young larvae are hatched within its shelter, and crawl out to reach their food plant. The female is a top-shaped (turbinate) creature encased in a leathery skin, more or less clothed with fine hairs, enveloped in a mealy secretion, with rows of fine spines on the dorsal surface of the abdominal segments, and the body terminating in two horny tails (anal appendages). The head is merged into the thoracic portion, and has the ventral surface wrinkled and bearing a rudimentary mouth; the antennae and legs are aborted. The only distinct specific characters are the dorsal spines and the form of the anal appendages. The males are delicate two-winged insects, with long antennae, slender legs, and the body very long and attenuated, ornamented with two fine filaments. They either form single short tubular galls on the leaves, or form masses of the same tubular galls; or they are placed in rows enfolded in a hood growing from the side of the female gall like a small cockscomb. All the members of this genus are confined to the eucalypts.

Apiomorpha duplex is the largest insect-gall in the world. Springing directly from the twig, it swells out into a stout four-sided gall, 1½ inches in diameter, 3 inches in length; beyond this the apex of the gall is produced into two stout flattened appendages extending another 9 inches. The enclosed female coccid measures up to 1½ inches. A. munita forms an angulated gall rounded at the base, with each angle on the apex furnished with a slender curled horn, but it is very variable both in form and size. A. pileata is an egg-shaped gall, with the apex truncate and forming two lips, the apical orifice forming a keyhole-like slit between them. We have two varieties of this gall, which in their immature state have a membranous tailed cap covering the apex which dries and falls off as the gall matures, leaving the apical orifice exposed. A. pomiformis is shaped like and about the size and shape of a small apple, with the apical orifice situated in a depression in the centre. It is a North Australian form, and is also found on stunted gums in the interior. Specimens of a large gall received from Tennant’s Creek, Central Australia, with the enclosed coccid, show that the structure of the coccid is very different from the Apiomorpha the anal extremity being thimble-shaped, fitting against the apical orifice, so it will require to be placed in a new genus. A. dipsaciformis is an oval gall covered with curled filaments like a “teasel.” In the group in which the male galls are formed on the side of the oval female gall, A. pharatrata is a typical form; the female gall is oval, overshadowed with the mushroom-shaped mass of coalesced tubular galls growing out near the apex.

The female coccids of the Genus Opisthoscelis, as they change from the larval stage, lose almost every vestige of the first two pairs of legs, while the hind pair are produced into long attenuated appendages, which in some species (when enclosed in the gall) curve round over the back like hairs; the whole insect is rounded or top-shaped, with a peg-shaped anal appendage. Thirteen species are described, all of which produce galls upon different species of eucalypts. Opisthoscelis subrotunda is our commonest species; the solid fleshy galls, about the size of a pea, often cover and abort much of the foliage of the infested tree. The short rounded coccid fits tightly to the cavity, and the opening, closed by the tip of the anal peg, is on the under side of the leaf. Schrader has described the male galls of this species, which are probably very rare, and I have never been able to discover them.

The short, slender, reddish, tubular galls of O. spinosa are as plentiful as the curious thorn-shaped female galls, which latter have the opening at the tip, and are common on the foliage of the large-leaved ironbark, Eucalyptus siderophloia, growing around Sydney. The female coccid, in this and several of the other gall-making coccids with the spine or thorn-shaped structure, is firmly attached to the sides and base of the cavity, and is difficult to remove without damage. The galls of the Genus Ascelis are often dissimilar in form; that of Ascelis praemollis is rounded, with the opening on the under side of the leaf, and except for the shape of the scar and larger size might without close examination be taken for that of Opisthoscelis subrotunda; but the enclosed insect is a very different looking creature; it is simply an irregular jelly-like mass, with a short peg-like structure rising from what looks to be the back, but is the tip of the abdomen; this structure is produced into three finger-like projections, which, holding a lump of gummy substance, plug up the basal opening in the gall. A. schraderi, which forms a circular, flattened, blister-like gall in the tissue of the leaves of Eucalyptus corymbosa, is more flattened, with the anal tail truncate at the apex, without the curious finger-like appendages, and the anal aperture as fine as a pin prick is on the upper surface of the leaf.

I have gone somewhat extensively into the description of these gall-making coccids, owing to the fact that they form such remarkable structures, and differ from all other solid galls in the fact that they are formed by the larvae and are not the result of eggs deposited beneath the plant tissue. Specialists in the study of vegetable growths may find some key to the mystery of gall development in this fact.

The Monophlebiinae comprises a number of large “mealy bugs,” so called because they form no protective scale, but are simply clothed with a mealy secretion, fine filaments or masses of felted wool. The females are often of considerable size, and during the greater part of their existence are capable of crawling about, but when adult and about to lay their eggs they often become fixed to the food plant. The males are of the usual two-winged type with long antennae and the tip of the abdomen fringed with fine filaments. This division has been cut up into a number of sub-families by Cockerell, and these divisions are given in Mrs. Fernald’s Catalogue, but here I propose to place them together under the one sub-family.

Monophlebus crawfordi is one of our largest species; the female measures about 1 inch in length and is broad in proportion; she is dull orange yellow marked with parallel bars of purple, and fringed round the edges with fine hairs; and is of a general flattened, broad, oval form, with the dorsal surface distinctly segmented. She is generally found clinging to the stem of a smooth-barked eucalyptus tree, sometimes half hidden under a bit of loose bark and surrounded with white mealy secretion. When egg-laying she sometimes produces a great quantity of fine curled cottony filaments forming a mass much larger than the original size of her body, under which the eggs are deposited.

The Genus Callipappus contains 6 Australian species; the females are flattened, oval, irregularly segmented coccids of a dull brown to purplish red tint, which are usually found crawling about on tree trunks. Callipappus australe was described by Maskell (Pro. Linn. Soc. N.S.W. 1890) under the generic name of Coelostoma, a group confined to N. Zealand. The male is a beautiful two-winged insect of a general deep red colour, the wings rose-pink, and the tip of the abdomen clothed with a large bunch of silky white filaments like a tuft of spun glass; from this latter character it has received the fanciful but rather appropriate name of the “Bird of Paradise Fly.” The female is of an oval, flattened form about an inch in length; the body is irregularly segmented and lightly clothed with flakes of a mealy secretion. When depositing her eggs, generally on the trunk of a tree, she becomes attached to the bark with a patch of silk on the ventral surface of the body; the body swells irregularly, the extremities of the abdomen shrink and turn upwards, the whole body later becoming simply a dry shell. Guérin described a species, C. westwoodi, from West Australia; and Fuller a few years ago re-described this and named two new species.

Icerya purchasi, known as the “Fluted or Cottony Cushion Scale,” was first described from New Zealand, but had been a well-known pest to the citrus orchards in California many years before it was discovered in New Zealand. The adult female is a very distinctive red coccid with black legs and antennae, and a dull red body with the thoracic portion flattened and fringed with hairs. She produces a quantity of felted woolly filaments forming a mass completely covering the abdomen, which is marked with well-defined parallel furrows and ridges; under this secretion the eggs are deposited. This scale is found upon several species of wattles (Acacia) in the neighbourhood of Sydney, and on the roses in the gardens. It does little or no harm in Australia, as it is very much affected by different species of parasites. Several other species placed by Maskell in this Genus have been removed. Palaeococcus nudata is one that he described from Australia on verbenas and cosmos. I found it to be very abundant on red clover in the Lismore district, N.S. Wales; it is a smaller oval species uniformly clothed with mealy secretion. P. rosae, described by Riley as Icerya rosae, the “Floridian Scale,” is a convex dull brown shining coccid with the outer margin fringed with short white tufts. Though originally described as a rose pest in Florida it is found upon Hakea and Grevillea bushes in the vicinity of Sydney.

These insects are wingless, with a more or less thin integument. The rather complicated sucking mouth is furnished with hooks; the thoracic segments are indistinctly divided, and the foot terminates in a single stout claw. They were usually placed at the end of the Hemiptera in the Order Parasita; but later investigators consider them so very closely allied to the true bugs that they are here placed as a Sub-Order. Burmeister called them Pediculina.

Family 1. Sucking Lice.
PEDICULIDAE.

These are purely parasitic upon animals, and derive their food from the blood of their hosts, which they obtain by puncturing the skin with their tubular sucking mouth. It is not an extensive family, containing only about 40 described species included in 6 genera, and they are widely distributed over the world.

Three species are known to live upon the clothes and skin of unclean men, the eggs of which, known as nits, are attached to the hairs of the animal or man infested. From their repulsive habits lice are not popular insects even for entomologists to take up. Nothing is known about those infesting the natives of Australia, though it is believed that the different races of man, particularly savage tribes, are infested with distinct species of these parasites.

The common head louse, Pediculus capitis, is confined to the fine hairs of the head, seldom or never going on the coarser hair of the body; the pale-coloured eggs are glued to the hairs, from which emerge larvae closely resembling the adults. Pediculus vestimenti lives in the clothes of unclean persons, only coming on the skin to suck up blood; it differs merely in being darker and broader in general appearance. The Crab-louse, Phthirius inguinalis, is a very short-bodied creature which clings with its large claws to the stouter hairs of the body. In ancient times all these were very common, and a loathsome disease called Phthiriasis was said to be due to them. The domestic animals, hogs, cattle, horses, &c., are infested with distinct species.

Sub-Order IV. MALLOPHAGA.
Biting Lice.

The classification in which this group should be placed is not yet definitely settled; Sharp places them in the Order Neuroptera between the Psocidae and the Termitidae: Cholodkovsky combines them with the sucking lice and creates a new Order, Pseudorhynchota (Zool. Anz. xxvii. 1903); while Kellogg has given them the rank of an Order under the group name Mallophaga.

They are certainly not lace-wings in the strict sense of the word; and their habits are so similar to those of the preceding division that I propose to place them as the fourth group of the Order Hemiptera.

They consist of biting lice infesting animals and birds, and feed chiefly upon the hair, feathers, scales, or excretions of their hosts by means of stout biting jaws, but are also said to be furnished with an apparatus enabling them sometimes to suck up the blood. They all have flattened bodies encased in horny integument, lightly clothed with stout hairs; the antenna contains from 3 to 5 short joints, and the eyes when visible are situated behind the antennae; the thorax is narrow, apparently composed of two divisions; the short stout legs are provided with 1 or 2 fine claws well adapted to their parasitic habits. The wings are wanting, and the oval abdomen contains from 9 to 10 segments. They attach their eggs to the hairs or feathers of their hosts, and the larvae develop upon the body.

Though some members of the group might be confounded with the Anoplura, they are easily distinguished from them by the structure of the mouth, and the different shaped claws at the extremity of the tarsi. While the sucking lice are always confined to a particular host, the biting lice are not so exclusive, for the same species may be found upon several dissimilar birds or animals, and it is not uncommon for several distinct species to infest the same host.

A number of European writers have studied and described these parasitic creatures; Denny (Monographia Anoplurorum Britanniae 1842) described all the British species, which he illustrated with coloured plates: Piaget’s “Le Pediculines,” Leyden 1880, is a more important work, and was followed by a supplement in 1885; the first contains a description of all the species known up to that date, and the second adds 100 new species which he had examined. Taschenberg in 1882 published a fine Monograph, which however was never completed.

In America the chief writers have been Osborn and Kellogg; the first in Bulletin 7, Division of Entomology U.S. 1891, dealing with “Insects affecting domestic animals, Chapter v., Mallophaga,” figures and describes a large number, among them some new species. Kellogg describes a great many new species (New Mallophaga i., ii., iii., 1886–89, Proceedings California Academy of Sciences, Vol. vi.), and also gives a great deal of information about the structure and classification of these insects. He says: “I propose therefore, in the light of the present position of the Mallophaga as an independent order of insects, to rank the Nitzschian families as sub-orders, the Nitzschian genera as families, and the Nitzschian sub-genera, the genera of the present day writers, as genera.”

In this classification two sub-orders are created, Ischnocera, containing two families, viz.: Trichodectidae, in which the members have 3 jointed antennae and tarsi with one claw, and found upon animals; and Philopteridae, lice with five jointed antennae and two tarsal claws, which infest birds. The second sub-order, Amblycera, also comprises two families, viz.: Gyropidae, with four jointed antennae and one tarsal claw, infesting animals; and second the Liotheidae, with four jointed antennae and two tarsal claws, chiefly found upon birds, but in Australia also found upon marsupials.

There are about 1,000 species of these lice described from all parts of the world, but the genera are few in number. Very little work has been done in Australia on the Mallophaga: Piaget described a species on the wombat for which he created the Genus Boopia, naming it B. tarsata (1880). In his Supplement (1885) he described a second on the red kangaroo as Boopia grandis; and others on Australian birds, among them Menopon infumatum on the “Laughing Jackass,” and Menopon pallipes on the “Swamp Quail.”

In 1902 (Victorian Naturalist) Messrs. Le Souëf and Buller published two papers dealing with these parasites; the first entitled “Descriptions of some Mallophaga on Australian Birds,” and a second “Descriptions of some new Mallophaga from Marsupials,” illustrated with drawings. They describe the kangaroo louse, Heterodoxus macropus, as common upon wallabies and kangaroos in most parts of Australia. The female is a pale chestnut-coloured insect about 1½ lines in length, with the typical conical blunt head, 4-jointed antenna, and elongate oval abdomen fringed with hairs, and barred with black between the segments. The Genus Boopia contains the wombat louse described by Piaget, and three other species found on wallabies. A fifth species, Latumcephalum macropus, is also parasitic upon wallabies. The Native Companion or Australian Crane is infested by a species described by these writers under the name of Lipeurus giganteum; it is of a uniform dull white colour, with an angular head, and measures ¼ of an inch in length. Three species are found upon the Lyre-bird, namely: Lipeurus menura, Nirmus menura, and Menopon menura. The white ibis has a distinct species, and another is found upon the sulphur-crested cockatoo. The emu is the host of an elongate dark-coloured species measuring up to 2 lines in length; the “Apostle Bird” and the “Rosella” parrot have each a distinct parasite.