These insects are named from χηλὴ, a forceps, and στόμα, a mouth,—in allusion to the forcipate form of the mandibles, which are strong, and cross each other in inaction.

They and the next genus are styled carpenter bees, but they are not more consistently thus called than might be Anthophora furcata and the genus Ceratina; they, in fact, like the latter, just as often avail themselves of an empty straw to form their cells in, or the cylinder that has been drilled by some xylophagous beetle of their own size, as they themselves drill into palings and solid wood for the purpose, but when they do this, it is facilitated to them by their powerful mandibles and their square and strong head. They are certainly very compactly formed, their structure being indicative of great power, of course relatively to their size. When they drill their cylinders themselves they are extremely persevering in its execution, and in the process, the material they extract, which is like fine sawdust, they withdraw from the depth of the cavity by passing it beneath them, and pushing it out at the orifice by means of their posterior legs and the apex of the abdomen, for they are too long to be able to turn within the cavity they have formed, its capacity not being sufficient to permit this, as it is very little larger in diameter than themselves. I have repeatedly watched them in these operations.

Having found or drilled a suitable cylindrical tube, they do nothing further to it but collect a sufficient store of provender for the nutriment of the young one, upon which they deposit the egg which is to produce it. The insect then flies away to collect a small quantity of clay intermingled with sand, and this they knead together by means of a viscous secretion which they disgorge, and this forms a concrete that hardens firmly and rapidly; to anticipate its rapid drying they speedily fly back, carrying this small ball within their mandibles, and with it they cover over the provision they have collected, and which, adhering to the sides of the cavity, forms a firm and hard division, effectually separating it from the next store of provision that is to be accumulated for the supply of the larva that will be hatched from the egg that is to be deposited, and the same process is repeated again and again until all the eggs are laid. In their development, which takes place near midsummer, the males precede the females by about ten days. They associate sometimes in colonies, often using the tubes of the straw thatch which covers cottages for their nidus.

These bees are subject to the parasitical intrusion of Fœnus jaculator and assectator, which I have repeatedly caught at Battersea, hovering opposite the cells of these insects bored in the shingles forming the enclosure of an old garden outhouse. These parasites are themselves peculiar creatures, forming a type distinct from the Ichneumons, and belonging to the group Aulacus, upon which see my paper in the ‘Entomologist,’ June, 1841. In these insects, the abdomen springs from immediately beneath the scutellum. Chrysis cyanea and ignita are also bred at the expense of these bees, neither of the species of which are uncommon; the smaller one, the C. campanularum, which is the smallest of our true bees, excepting perhaps one or two of the Nomadæ, I used to find in abundance upon the railings of the fields that skirt Hampstead Heath, on the right-hand going from London, parallel with the Vale of Health, and thence rising to the Holly enclosure of the Earl of Mansfield’s mansion. This spot has been productive to me of many very choice aculeate Hymenoptera, and supplied me with them in abundance at a time when even the chief metropolitan collections were bare of them. It has also furnished me with several very desirable Diptera of extremely rare genera. The male of the larger species of this genus Linnæus called florisomne, from its habit of curling up its abdomen and antennæ, and passing the night in flowers. Those which they chiefly frequent are the species of Wallflower, and the Campanula, especially the round-leaved Throatwort.

Gen. Char.: Body glabrous and much punctured. Head globose and curving to the thorax posteriorly; ocelli in a triangle far forward on the vertex; antennæ slightly subclavate, the scape not half so long as the flagellum, the first joint of which is robust, subclavate, and twice the length of the second, which, with the rest, are subequal, very slightly lengthening to the terminal one, which is as long as the basal one and laterally compressed; face slightly convex, cheeks large and convex; clypeus lunulate, convex, and with two minute central teeth on its front margin; labrum longitudinally oblong, rather broadest at the base and slightly waved laterally, concavo-convex and subemarginate at the apex; mandibles subequal, tridentate at the apex, and the central tooth obtuse; cibarial apparatus moderately long, tongue twice the length of the labium, with a small knob at its apex; paraglossæ very short, almost obsolete, coadunate at the base; labial palpi two-thirds the length of the tongue, the two first joints membranous and long, the first one-third the length of the second, which tapers to its acute extremity, before the end of which the two terminal, subclavate, very short, subequal joints are inserted; labium half the length of the tongue, slightly produced in the centre of its inosculation; maxillæ subhastate, two-thirds the length of the tongue; maxillary palpi three-jointed, short, robust, equal, and collectively subfusiform, the terminal one rather acute. Thorax globose; prothorax inconspicuous; scutellum lunulate; post-scutellum linear, transverse; metathorax declining; wings with two submarginal cells, and the commencement of a third indicated, the second larger than the first, subtriangular, and receiving both the recurrent nervures, one at each of its extremities; legs short, rather robust, subsetose and spinulose; posterior tibiæ convex externally and with their plantæ rugose, the latter covered beneath with a dense brush of short hair; claws simple. Abdomen cylindrical, convex above, retuse at the base, and the first and second segments slightly constricted at their extremity, obtuse, and from the end of the third segment sensibly declining to the apex; plane on the venter, where, from the second segment, the plate of each, excepting the glabrous terminal one, is covered with a dense brush of short hair for the conveyance of pollen.

The MALE differs in the antennæ being rather longer, more distinctly filiform, the seventh segment of the abdomen concealed under the extremity of the sixth, and the venter from the third segment longitudinally deeply concave, the plate of the third itself covered with hair; the claws more robust and each equally bifid, not bidentate.

The names of insects are not always very aptly given, for the only available derivation of this appears to be from ἔπιον, wool; in allusion to the clothing of its venter; but, if so, it should be spelt without the H, for the first letter is without an aspiration. The habits of these closely resemble those of the preceding genus, to which they have a great personal likeness, and therefore their natural history would be but its reiteration. Our solitary species is a rare insect, but I expect western England would produce it. It is like those of the preceding genus, of a uniform black colour, punctured, but it approximates more closely than they do to the type of form exhibited in the genus Osmia. They visit the same flowers as the preceding genus.

Gen. Char.: Body glabrous, subpubescent, shining. Head subglobose, as wide as the thorax; ocelli placed in a slight curve on the summit of the vertex; antennæ short, geniculated, the flagellum subclavate seen in front, but seen from above, owing to the compression of the terminal joint, subfusiform, the first joint of the flagellum globose, rather robust, the second short, subclavate and subequal with the rest, which increase gradually in length and substance to the terminal one, which is the longest, and laterally compressed; face flattish; clypeus subquadrate, very convex and very pubescent; “labrum oblong, quadrate; mandibles strong, tridentate; labium (tongue) long, filiform; labial palpi having the third joint articulated externally on the outer side of the second; maxillary palpi four-jointed.” Thorax globose; scutellum lunate; post-scutellum transverse, linear; metathorax rounded; wings with two submarginal cells and the commencement of a third just indicated, the second very slightly larger than the first, and receiving both the recurrent nervures, the first just beyond its commencement and the second close to its termination; legs short, rather robust, subsetose; the posterior tibiæ externally convex and the posterior plantæ with a dense, short brush beneath; the claws simple. Abdomen cylindrical, retuse at the base, convex above, declining from the base of the fourth segment to the extremity, the first and second segments very slightly constricted, the margin of the posterior one, at the apex, slightly crenulated, the ventral segments plane and from the second covered with a dense brush of parallel hair, excepting the sixth, which is reflected laterally and longitudinally, convex down the centre.

The MALE differs in having “the sixth segment of the abdomen emarginate, and with a strong tooth on each side; the terminal segment emarginate, thus producing two strong, lateral, obtuse teeth, the ventral plates of these same segments emarginate at the extremity, and the emargination fringed with hair; the claws bifid.”

Named by St. Fargeau from ανθος, a flower, and κοπὴ, a cutting or incision, from its habit of cutting sections out of the petals of the common scarlet poppy with which to line the cells it forms within the cylinder it excavates, just as Megachile does with the leaves of various plants. It is noticed as British upon the faith of the specimens introduced by Leach into the cabinets of the British Museum and presumptively caught in the west or south-west of England, a region rich in rarities. Rennie in fact tells us that he has found it at Largs, in Scotland. One of Leach’s specimens I received in exchange from that establishment in 1842, and which is now in the possession of Mr. Desvignes, to whom my collections passed in the following year. This genus forms a sort of combination between the genera Megachile and Osmia, it having the upholstering habits of the former in the mode with which it lines its nest, and the general habit of the latter. At a first glance, before its habits were known or its structure examined, even an experienced entomologist might have placed it under Osmia, as an unrecognised species, for it very strongly resembles the Osmia leucomelana. This proves how very inconclusive habit is as an index to habits, the latter of these insects drilling into the pith of brambles, and the Anthocopa tunnelling cylinders into the hardest trodden roads or pathways and lining them with its crimson hangings.

From the extreme rarity of the insect, I have been unable to examine the cibarial apparatus, and thence to ascertain upon what substantial grounds the generic distinctions are based, which separate it from Osmia. Whether it was these mere habits of the insect which induced Le Pelletier de St. Fargeau to establish the genus I do not know, but he is always extremely slovenly, and therefore very unsatisfactory in his characteristics, which are never framed in a strictly explicit manner. In consequence of all these difficulties, I have merely been able under the generic character to introduce such as he has given, which I could not derive from the personal external inspection of Mr. Desvignes’ female (my own selection of whose bees for the purposes of this work he has been so kind as to lend me, and whom I thus publicly present with my best thanks). I have therefore compounded a character as well as I could from St. Fargeau’s descriptions, inserted in the tenth volume of the ‘Encyclopédie Méthodique,’ and from his work on the Hymenoptera, forming one of the ‘Suites à Buffon.’

The habits of these bees, as said above, are to excavate vertical cylinders in hard down-trodden pathways and roads, by the sides of fields where corn is grown, and where consequently the common red poppy is abundant. From the petals of the flowers of this plant they cut out semicircular pieces, precisely as is done by Megachile with the more rigid leaves of shrubs and trees, and convey them home and line their nests with them, just as is practised by that genus with those leaves,—with this difference merely, that a sufficient portion of the upper edge of the pieces of the petals used is left projecting, for the purpose of forming a covercle to the nidus, and which, when filled with provender and the egg deposited, is refolded over it and covered in, and it is closed up with earth. They then proceed to make another excavation, which is treated in the same manner, for they deposit only one larva in a tube. If disturbed in their retreat, they will show themselves at its mouth, like Dasypoda, to see what is the matter.

I would urge our collecting entomologists, especially those who have the opportunity of hunting up the west of England, to use due diligence and strive to confirm the native existence of this bee and add specimens to the cabinets of their fellow-entomologists.

Gen. Char.: Head subglobose, concave, posteriorly fitting the prothorax and about as wide as the thorax; ocelli placed far forward on the vertex, which is wide and convex, in a curved line; antennæ filiform, sometimes subclavate, short, and geniculated, the scape robust, as long as the four following joints, the basal joint of the flagellum globose, its second joint clavate and as long as the terminal one, the remainder short, subequal, and gradually but slightly increasing in length; the face flattish; the clypeus a truncated triangle, convex; labrum longitudinally oblong, a little laterally distended at the articulation, from whence the sides are parallel; mandibles broad at the apex, obscurely tridentate, the internal teeth obtuse and short; cibarial apparatus long; the tongue three times the length of the labium, clothed with short hair and tapering from the base to the acute apex; paraglossæ very short, coadunate at the base and acuminate at the apex; labial palpi more than half the length of the tongue, the two first joints membranous and long, the basal one the broadest, seated on a petiole and not so long as the second, which tapers to an acute point, before the apex of which the remaining two short subclavate conterminous joints articulate; labium about one-third the length of the tongue, acutely produced in the centre of its inosculation; maxillæ as long as the tongue, subhastate and acuminate; maxillary palpi four-jointed, rather short, the joints subequal and subclavate, but the second is both the most robust and slightly the longest. Thorax oval or globose; prothorax inconspicuous; scutellum lunulate and convex; post-scutellum transverse and linear; the metathorax abruptly truncated; wings with two submarginal cells, and a third distinctly commenced, the second the longest, and receiving both the recurrent nervures, the first towards its centre and the second near its termination; legs moderate, setose, the plantæ of all with a dense brush beneath; claw-joint longer than the three preceding; claws simple. Abdomen short, cylindrical, convex, the terminal segment slightly pointed, the ventral segments densely pilose in parallel lines from the second.

The MALE differs in having the antennæ longer and always filiform, the ventral segments very concave, and the terminal dorsal segment variously mucronated, tuberculated, spinose or serrated, and the claws bifid.

Named from ὀσμὴ, sweet-scent, from some fancied idea of their possessing the property of emitting a sweet odour; but this, although it is the case with many of the bees,—for instance, with the genera Prosopis, Halictus, Nomada, some of the Anthophoræ, Saropoda, and the male Bombi and Apathi,—I have not noticed in any of this subsection, the Dasygasters, and therefore not in any of the present genus. It is possible that when richly laden with pollen, this may emit some smell, but I am not aware that any of the scent of flowers lies in the anthers or their pollen, although this in some cases has a spermatic odour pointing to its express function; but be this as it may, such is their name. These as a group are what are called the ‘Mason Bees,’ from the habit they have of agglutinating particles of sand or earth mixed with minute pebbles, scarcely larger than grains of sand, or raspings of wood combined in the same manner, with a secretion which they emit, and of which they form their cells. The instinct of the creature prompts it to be speedy in the operation, as the material, like plaster of Paris, dries very rapidly to a hard substance. Whether they have the power of softening the edges as the manufacture of the cell proceeds is not known, nor whether, as they add the material, it instantaneously consolidates itself, but the colour of the structures themselves would indicate a simultaneous mixture. This could not be the case, if the mortar or mixture were formed away from the domicile and brought home in little pellets, each being added upon the insects’ arrival, although they obtain it all from the same spot, whence arises its uniformity in colour, and they are speedy in the formation of their nests. These cells are rather rough externally, according to the nature of the material of which they are composed, but they are very smooth within. The nature of the cells varies with the places of their deposit, which is dependent upon the idiosyncrasy of the species. Thus, those which construct their cells in wood, form them of moistened particles of wood, and those which make them in cavities of any kind, in the earth, beneath stones, or within empty snail-shells, make a mortar of earth and sand and small pebbles. Some are strictly uniform in the selection of the material wherein they build, but others are perfectly indifferent to its locality, and adopt either earth or wood, and sometimes the mortar of walls, sandbanks or chalk cliffs. According to the nature or the size of the receptacle which they select, is the adjustment of these cells. Where the cavity is restricted they place them end to end, but where it is more roomy they affix them side to side, completely adapting themselves to the circumstances of the locality as I shall instance below, in the description of the special habits of the more conspicuous species. I have elsewhere referred to the metallic colouring of many of the species of this genus, and amongst them is found the greatest sexual disparity of personal appearance, the O. leucomelana, and one or two of the neighbouring species being, perhaps, the only ones wherein uniformity of appearance would unite the partners together. The majority are very pubescent insects, and the females of the terminal species in the foregoing list are remarkable for a couple of inwardly curved horns, springing from the base of the clypeus just below the insertion of the antennæ, an appendage usually a male attribute.

There is very great dissimilarity in the habits of the various species, whence no single characteristic will embrace them, nor is there any distinctive feature whereby the genus might bear subdivision, either from habits or habit, as will be collected from the following cursory survey of their special natural history.

Thus the first species, the O. leucomelana, named so from the white decumbent down which edges the black segments of the abdomen, extracts the pith from bramble sticks, and its cells are formed and closed with a composition made of triturated wood or leaves. The cylinders it forms are usually about five inches deep, and within this it constructs about the same number of cells proportionate to the small size of the insect. These are midsummer insects, coming forth in June and July; they are very local, but seem to abound in the vicinity of Bristol, whence Mr. Thwaites formerly sent me specimens. A very few days serve for the hatching of the larva, which spins a slight silken cocoon, and in this dormitory it reposes until its season again comes round. Under the influence of the following first genial spring weather, the larva is transmuted into the pupa, and the active little imago comes forth upon the settlement of our variable spring, in the merry days of June, and thus is perpetuated the circle of its existence, but which is sometimes abridged by its special parasite, the pretty little Stelis octomaculata. Many of the species in the males are distinguished by a peculiar armature of the apex of the abdomen; the second being named by Kirby from the circumstance. A very remarkable singularity distinguishes the males of the third species, in the fringe of short hair that runs along the flagellum of its antennæ. This, I believe, was first noticed by the late Mr. Bainbridge, a very active practical entomologist, who took the insect at Darenth or Birchwood, and distributed specimens with this manuscript name attached, which has since been appropriated by another entomologist to whom the science was wholly unknown at that time, but as it is scarcely consistent with scientific courtesy to adopt such a course, and as the MS. names of Linnæus and Kirby have been retained, where it was authorized by their being attached to undescribed species, I have restored to Mr. Bainbridge his just rights, and have claimed the same for myself, in the case of Andrena longipes, and which many cabinets must still possess with my name attached, in my own writing, unless their possessors have chosen to adopt the illegitimate parentage; for the entomologists of my own standing well know that I always freely distributed specimens to all who desired them of the many very desirable insects which I have captured in the course of my entomological career. The fourth and the ninth species, the O. bicolor and O. aurulenta, have very much the same habits, both usually burrowing in sandbanks, sometimes however in wood, in which case the perforation, contrary to the mode of wood-drilling bees, is made upwards, a sagacity or instinct which saves it much trouble, for the particles as they are removed by the mandibles are passed beneath the insect, and their own gravity carries them downwards, and thus the insect saves itself the labour of conveying them out as they accumulate in inconvenient quantities. The cells in this case are placed end to end. When they burrow in the earth, the latter species often associate gregariously in large numbers, and if they select a cavity, instead of tunnelling it themselves, and it be too large to take one cell upon the others, they form them side by side, and thus fill the space. This is the case when they adopt snail-shells as the receptacle for their incunabula, and this is done by both these species, and the shells they select are the empty ones of Helix nemoralis, hortensis, and adspersa. The capacity of the latter shell being much greater than that of the others, and too wide for a single succession, she fills the interval by placing them side by side, and with the increase of the whorl of the shell towards its orifice she places them across the space, and thus completes her task. In the former shells, the cavity at first admits of the succession of but one upon the other, but with its enlargement she places them side by side, and this repeated fills the hollow. Its aperture is then closed with earth and pebbles or sticks agglutinated together, as described at the commencement. The O. fulviventris burrows in wood, and upon this species the Stelis phæoptera is parasitical; and that very pretty but extremely common species the O. ænea, in which the male is of a rich bronzy tint, and the female of a beautiful blue, verging sometimes to nearly black, burrows also in wood, although sometimes it capriciously selects old walls or chalk-cliffs, and is subject to the incursions of the same parasite. Perhaps the most extraordinary species is the O. parietina, figured and named by Curtis, and which he first found at Ambleside; it has since been found in the Grampians very considerably above the level of the sea, and it is thus essentially a northern species both from altitude and locality. It would appear that this species selects some flat stone of about a foot in surface, lying upon the ground over a hollow spot. Such a specimen, sent to the British Museum, had attached to its under side two hundred and thirty cocoons, indicative of a considerable colony, or perhaps the accumulation of successive years, as one-third of these cocoons were empty of tenants. These, in their new depository, continued developing themselves in the perfect state between March and June, males appearing first. When the transformations of the season ceased, five-and-thirty were still left to present themselves another year, and the following spring these were developed; thus, including those which had already escaped when the stone and its treasure was secured, three successive seasons were occupied in their transmutations. It may be a species that requires three years for its metamorphosis, and the whole deposit of cocoons may have been the result of three years’ accumulative structure, the vital activity of their northern life being perhaps more sluggish than in species frequenting the south. The last species the O. rufa, that in which the female is remarkable for its inverted horns, which must be for some use in its economy, is perhaps the most common of all. I have found it in abundance upon old walls with a sunny aspect at Erith, and throughout the pleasant Crays of Kent. It is indifferent as to the choice of its domicile, selecting either walls, where I have chiefly found them, sandbanks, or the decaying stumps of pollard-willows. Its processes are similar to those of some of the earlier described, but its larva is longer in full feeding, which, when it has consumed all its provender spins a tough cocoon of brown silk, wherein it undergoes its changes; some, depending much upon locality, pass into pupæ in the autumn, others hibernate as larvæ which are subject to destruction from the attacks of the Chalcideous insect, Monodontomerus dentipes, previously noticed under Anthophora. Some of the Chrysididæ also infest several of the species of this genus, and I have no doubt that Stelis aterrima is parasitical upon one of them, although it has not been recorded. The various species frequent many flowers, especially those abundant in the locality they inhabit, but the O. pilicornis chiefly affects the common Bugle (Ajuga reptans), and they much frequent composite flowers, especially the species of the genus Hieracium.

Gen. Char.: Body subhirsute. Head subglobose; vertex broad, glabrous, with a deeply impressed cross upon its summit, in the centre of which the ocelli are placed in an almost straight line and contiguously; antennæ short, filiform, geniculated, the scape slightly curved, the basal joint of the flagellum subglobose, its second joint as long as the terminal one and subclavate, the rest short, subequal, but gradually increasing in length to the terminal one, which is laterally compressed; the face flat; clypeus transversely lunate but straight in front; labrum lunulate, tuberculated laterally; mandibles broad and obscurely bidentate; cibarial apparatus moderate; tongue twice the length of the labium, tapering from base to apex, where it terminates in a small knob, and is clothed with short hair; paraglossæ obsolete; labial palpi as long as the tongue, the two first joints long and membranous and tapering to the apex of the second, which is acute, and about one-fourth the length of the first, it has the two very short, subclavate, terminal joints, which are conterminous, and articulated just before its acute apex; maxillæ subhastate and acuminate; maxillary palpi very short, linear, and equal. Thorax globose, pubescent, concealing its divisions; metathorax truncated; wings with three submarginal cells nearly equal, or the third the largest, the second receiving the first recurrent nervure at about one-third its length, and the second is received by the third submarginal cell near its extremity; legs setose; the posterior tibiæ convex, very slightly enlarging from base to apex, rounded at the extremity externally, and unfurnished with means to convey pollen; posterior plantæ oblong, narrowly equal, and not auriculated; claws bifid. Abdomen ovate, convex above, deflecting toward its extremity, and subglabrous on the disk, the terminal dorsal segment triangular, and its ventral plate straight at its apex with the lateral angles reflected, making it concave beneath and subcarinated longitudinally in the centre, or also triangular and the sides of the prominent angle deflected.

The MALE differs in having the antennæ slightly longer, in being rather more pubescent, more highly and rather differently coloured, and its terminal segment merely rounded.

Named from α, privative, πάθος, affection; that is to say, without affection, from their habit of leaving their young to be nurtured by others, in allusion to their parasitical instincts, for the young of these bees are brought up in the nests of the Bombi. They form the only instance in bee-parasitism of the parasite closely, or nearly so, resembling its sitos, if not always in colour, certainly in habit. Having no labours to undergo they consist of merely males and females, but the latter, although very like the large female Bombi, are much less pubescent than these, for they have a broad disk, upon the upper surface of the abdomen, always smooth and shining. Both sexes appear to have free in- and egress to the nests of those Bombi which they infest, without any let or hindrance on the part of the latter, with whom they seem to dwell in perfect amity. In the times of their appearance they closely resemble the Halicti and the neighbouring Bombi. Thus the females, after impregnation in the autumn, having hibernated during the winter in selected receptacles, come out with the first gleams of spring conjunctively with the large maternal Bombi, in whose nests they have taken their long repose in perfect torpidity; and as soon as these begin to accumulate the masses of conglomerated honey and pollen whereon to deposit their eggs, the parasite takes advantage of it, lays her eggs too, and thus secures food for her offspring. There being two broods of them in the year, many are gradually developed with the advance of summer, but the great hatching takes place in the autumn, when the thistles are in blossom. Then both males and females come forth in abundance, the latter are made fertile, and their partners enjoy the brief interval of the still blossoming flowers until the usual period is put to their existence by natural decay, the first frosts, or the rapacity of insectivorous birds. Connected with this last circumstance I have a personal experience to record, and which its repetition would indicate as being one of Nature’s prompting acts. A lofty sandy level, very near the high-road which leads at the upper part of Hampstead Heath, to Highgate, from which road it was separated by merely a band of whins and coarse grass, used to be a very favourite collecting place of mine, for there, and in its immediate vicinity, I have often caught, within a very brief period, more than half the genera, and a very large number of the species of the fossorial Hymenoptera. One particular little spot was inhabited by Psen equestris, rare everywhere else, and our largest Cerceris, who carried on their instinctive pursuits during all the summer months, but at a particular time in the autumn, varying slightly with the nature of the season, a flock of wagtails (Motacilla) would alight and make brief work of those fossores which were still aflight; and this was repeated season after season, as if the wagtails thought it was time that their own rapacity should stop the course of these predacious insects. But to return, the female Apathi then resort to the nests of the Bombi whence they have issued, and lay themselves up in their winter dormitory. That this must take place speedily after impregnation is rendered almost conclusive by the fine state in which their pubescence appears in the spring, which would be tarnished did they loiter about visiting flowers previous to their return home. But the labours of the female and neuter Bombi themselves are now over, and they would therefore find no store whereon to deposit their eggs. The parasitical allocation of these insects is as follows. Apathus rupestris infests Bombus lapidarius; A. vestalis the B. terrestris, and this forms an instance in which the parasite is not clothed in the colours of its sitos. But A. Barbutellus has a wide range, for it frequents the nests of B. pratorum, B. Derhamellus, and B. Skrimshiranus.

Gen. Char.: Body densely hirsute. Head small, subglobose, not so wide as the thorax; the vertex glabrous, with a longitudinal, short, deep channel, crossed in its centre by a deeper transverse one, wherein the ocelli are disposed in a very slightly-curved line; antennæ short, geniculated, and filiform; the scape half as long as the flagellum, the first joint of which is globose, the second subclavate, the rest short and subequal, and the terminal one compressed laterally; face flat, densely pubescent; clypeus subtriangular, gibbous, its base truncated, and apex convexly lobated, or straight and margined; labrum lunulate; mandibles broad at the base, and obscurely tridentate; cibarial apparatus moderate; tongue twice the length of the labium, clothed with pubescence to within a brief distance of its apex, and terminating in a small knob; paraglossæ about one-fourth the length of the tongue, coadunate at the base, and acuminate; labial palpi three-fourths the length of the tongue, broad at the base, and tapering to the extremity of the acute apex of the second joint, which is about one-fifth the length of the first, the two terminal joints very short and articulated laterally just before the end of the second; labium one-half the length of the tongue, broadest at its base, and acutely produced in the centre of its inosculation; maxillæ as long as the tongue, subhastate and acuminate; maxillary palpi two-jointed, short, sometimes equal, and slightly robust, or with the basal joint very robust, and its terminal joint twice as long and linear. Thorax globose, very hirsute, whence its divisions are inconspicuous; scutellum lunate; metathorax truncated; wings with three submarginal cells subequal, or the third the longest, and a fourth slightly commenced, the second receiving the first recurrent nervure near its centre, and the third receiving the second recurrent nervure close to its extremity; legs robust, pilose, the four anterior plantæ with a dense, short, setose brush beneath; the posterior tibiæ triangular, very smooth, and irregularly concave on their external surface, fringed with long pile along its two external edges, and its extremity tipped with a short pecten of stiff setæ; the plantæ elongate and broad, nearly equal, externally shagreened and spinulose, with a longish auriculated process at the external angle of the superior edge, a dense brush of short, stiff hair beneath, and a short pecten of stiff setæ edging its subemarginate extremity; the claw-joint the longest of the four short subsequent joints, and the claws bifid. Abdomen ovate or globose, deflected towards its extremity, its base retuse, the last segment triangular, and terminating obtusely.

The MALE differs in always being more intensely coloured; in having the antennæ distinctly longer, less distinctly geniculated, the scape shorter, the third joint of the flagellum almost as short as its basal joint, and the fourth as long as the terminal one, which latter two are the longest of all, and the joints from the fourth to the eleventh severally more or less slightly curved.