In the Hemileucidæ there is a pair of lateral osmeteria, on the 1st and on the 7th abdominal segments, which however, are not highly colored (Figs. 363, 366, 10). In Megalopyge (Lagoa, Fig. 364) there is a lateral row of singular pale permanently everted processes which appear to be the homologues of the osmeteria of larvæ of other lepidopterous families. As these are repeated on seven segments, their metameric arrangement is obvious. The relation of these curious glands to the viscera is seen in Fig. 297, lgp, and their minute structure in Fig. 365.

At A, the lumen (l) is a deep narrow cavity, with the secretion (secr.), collected at the mouth of the cavity, composed of a thin, mucus-like, coagulated fluid, containing granules of varying degrees of fineness, which take the stain readily. Outside of these are collected fine nuclei (bc), stained dark, and enveloped in a slight, transparent, pale, protoplasmic envelope, which may be blood corpuscles. The glandular cells themselves are simply modified hypodermal cells, as seen at C. In some of the nuclei, indistinct nucleoli are seen, and deeply stained granules, especially around the periphery of the nuclei. At B is represented a section on one side of the middle, but still showing the spacious lumen. In the section represented by C, the knife passed through the process still nearer the outer edge, and near the base; at C¹, three of the glandular cells, with their large, deeply stained nuclei, are drawn. A transverse section at D shows the large lumen or cavity (l).

As to the function and homologies of these structures, it is difficult to decide. We have never noticed that they give off any odor, though they may prove to be repugnatorial; they are not visible in the fully grown, living insect, being concealed by the long, dense hairs clothing the body; they are not spraying organs, as they are imperforate at the end, not ending as the lateral, eversible glands of Hyperchiria io, etc., in a crateriform orifice.

They may be permanently everted glands, or osmeteria, which have, by disuse, lost their power of retraction and their crateriform opening, as well as the power of secreting a malodorous fluid.

In certain of the butterflies, the Heliconidæ (Colænis, Heliconius, Euides, and Dione), there is thrust from the end of the abdomen a pair of large, irregular, rounded, eversible glands, which give out a disagreeable odor, and are consequently repellent, and which seem to be the homologues of the odoriferous glands of other butterflies.

The large, soft, rounded, eversible glands, looking like puff-balls or a rounded pudding (Fig. 366, 12), are everted, when the butterflies are roughly seized, from the dorsal side of the penultimate segment of the abdomen. The males possess two smaller tubercles on the inside of the anal claspers or lobes. Müller also detected, in the females of various species of the Heliconidæ enumerated above, a pair of club-shaped processes like the balancers of flies, which are thrust out on each side of and under the odoriferous puff-balls of the hinder edge of the penultimate segment (Fig. 366, 13). The club or head is armed with hairs or bristles, which, in Heliconius, are like the scales of a butterfly.

In the caterpillars of certain blue butterflies (Lycænidæ) is an internal osmeterium, being a very minute sac which is everted from a transverse slit on the top of the 7th abdominal segment. Its function is quite the opposite of those of the caterpillars of other families, since the sac exudes a sweet fluid very attractive to ants, which may be diffused more widely by the delicate spinulose bristles crowning the summit. W. H. Edwards states that in several species of Lycæna, besides that on the 7th abdominal segment, there is on the 8th segment a pair of minute dorsal evaginable tubercles.

A pair of small ramose odoriferous glands are said by Siebold, who regarded them as alluring glands, to occur in Argynnis, Melitæa, and Zygæna, to be situated near the orifice of the oviduct, and Scudder has detected them near the anus of the female pupa of Danais archippus. The appearance of the odoriferous glands in the pupa of Vanessa io is well shown by Jackson (Fig. 366, 14). They develop as two tubular ingrowths of the hypodermis, perfectly distinct one from the other, each having its own separate aperture to the exterior. In Fig. 366, 14 the condition of parts is nearly as in the imago, the glands being situated below the rectum and opening of the oviduct. In both sexes of another Brazilian butterfly (Didonis biblis) on the median line of the abdomen between the 4th and 5th segments are two roundish vesicles covered with short gray hairs, which emit a disagreeable smell.

It is possible that the dark-green fluid in Parnassius, secreted by an evaginable gland, and which is moulded into shape by the scimetar-shaped peraplast (Scudder), is formed by the homologues of the anal glands of other butterflies.

A. Larval Insects

a. Each thoracic segment; sternal. Phryganea grandis.

b. Prothoracic, sternal, discharging a lateral jet of spray; with a single large internal sack.

LEPIDOPTERA

Family Tineidæ

Hyponomeuta evonymella.

Family Noctuidæ

Bryophila, Cucullia formosa, C. scrophulariæ, Habrostola, Cleophana linariæ, Catocala (sp.), Aporia cratægæ, Aplecta nebulosa, Leucania staminea, L. hispanica, L. nonagrioides, Plusia gamma.

Family Notodontidæ

Pheosia rimosa, Schizura concinna, Danima Banksii (Australia), Macrurocampa marthesia, Heterocampa pulverea, Cerura vinula, C. furcula, C. borealis, C. multiscripta.

Family Nymphalidæ

Probably all the species.

c. Prothoracic, dorsal; sending out a V-shaped odoriferous organ (osmeterium).

Family Papilionidæ

All the species as a rule.

d. Thoracic sternal, evaginable glands.

Family Perophoridæ

Lacosoma chirodota, Perophora melsheimerii.

Family Nolidæ

In three, and probably in all the species of Nola.

e. Lateral, abdominal, non-eversible glands, one near each spiracle, emitting a clear fluid.

Family Tenthredinidæ

Cræsus septentrionalis, C. varus, Cimbex americana, C. betulæ, Trichiosoma.

f. Lateral, abdominal, partly eversible glands emitting neither moisture nor odor, but flesh-colored.

Family Tineidæ

Phyllocnistis? (eight pairs.)

Hyperchiria io (two pairs, viz. on 1st and 7th segments), H. sp. (Mexico), Hemileuca yavapai, pamina, H. maia, H. artemis, Pseudohazis eglanterina.

g. Lateral, abdominal, permanently everted, metameric glands, not known to secrete a fluid, nor to be odoriferous.

Family Megalopygidæ

Megalopyge crispata.

h. Medio-dorsal, partly eversible glands, emitting a spray of liquid but no odor(?), and colored coral-red or orange-yellow (P. auriflua), but usually in the European species yellowish.

Family Liparidæ

All the species except those of Demas.

i. A single, median, abdominal, dorsal gland, emitting a fluid attractive to ants, on 7th segment; with a pair of minute, index glands on the 8th segment.

Family Lycænidæ

All the species.

j. Protrusile organs near the anus.

Myrmeleon larva (Hagen? Dimmock).

B. Nymph of Heterometabolous Insects

a. Paired, dorsal glands, on abdominal segments 1, 2, and 3.

Cimex lectularius (Künckel).

b. The same on abdominal segment 5.

Lachnus strobi.

C. Pupa of Certain Bombyces

At anterior end of certain pupæ, internal glands to moisten threads of the cocoon for exit of moth.

D. Adult Insects

a. Occurring on the prothorax only; strongly repugnatorial, best developed in ♂.

Anisomorpha buprestoides, Autolyca pallidicornis, Phasma putidum, Phyllium (sp.), Heteropteryx (sp.), Diapheromera femoratum (probably in all the species of the family), Mantis carolina.

b. Occurring on the pro- and mesothorax, and on the middle of the abdomen, orange-yellow, fleshy tubercles or evaginations.

Malachius bipustulatus, Anthocomus equestris, Evæus thoracicus.

c. Segmental, eversible glands, homologues of the coxal glands of other Arthropods, occurring on all, or nearly all, the abdominal segments.

Scolopendrella immaculata (coxal glands on 3d to 11th pair of legs), Campodea staphylinus (a pair of coxal glands on 1st to 8th abdominal segments), Machilis maritima (eversible, coxal glands on segments 1–7).

d. Occurring in the abdomen.

d¹. In the two first abdominal segments.

Corydia carunculigera ♂ and ♀.

d². Alluring (?) organs situated on the dorsal side of the abdomen, in the 6th, or 6th and 7th, abdominal segment.

Periplaneta americana ♂, P. orientalis (nymph), P. decorata ♂ (nymph), Ectoblatta germanica ♂, Ectobia lapponica ♂, Phyllodromia ♂, Aphlebia bivittata ♂, Platyzosteria ingens (on seventh segment).

e. At the end of the body.

Colænis julia ♀ (F. Müller), Heliconius apseudes (F. Müller).

LITERATURE ON DEFENSIVE OR REPUGNATORIAL GLANDS

Aldrovandus, U. De animalibus insectis libri septem cum singulorum iconibus ad vivum expressis. (Denuo impress: Bonon. apud Clementem Ferronium, 1638, p. 273. The first edition was in 1602.)

Moufet, T. Insectorum sive minimorum animalium theatrum, etc. London, 1634, pp. 185, 186.

Gœdart, J. Metamorphosis naturalis sive insectorum historia, etc. Amstelodami, 1700, Pars ii, p. 136. (French ed. of 1700, ii, p. 162; Lister’s Latin ed., London, 1685, p. 60.)

Réaumur, R. A. F. Mémoires pour servir à l’histoire des insectes, etc. Paris, 1736, ii, pp. 266–269, Pls. 21, 22. [ii, partie ii, pp. 21–23, of the Amsterdam ed. of 1737–1748.]

De Geer, C. Observation sur la propriété singulière qu’ont les grandes chenilles à quatorze jambes et à double queue, du saule, de seringuer de la liqueur. (Mém. sav. étrang, Paris, 1750, i, pp. 530, 531, Pl.; Goetze und Bonnet, etc., Auserlesene Abhandlungen, 1774, p. 220.)

Schaeffer, J. C. Neuendeckte Theile an Raupen und Zweyfaltern, etc. Regensburg, 1754.

Sulzer, J. H. Die Kennzeichen der Insekten, etc. Zürich, 1761, pp. 65–67, Taf. 5, Fig. 34.

Müller, O. F. Pile-larven med dobbelt Hale, og dens Phalæne, etc. Kjöbenhavn, 1772, pp. 53–56, Pl. 2, Figs. 3–5.

Bonnet, C. Mémoire sur une nouvelle partie commune à plusieurs espèces de chenilles. (Mém. math. d. savants étrang., Paris, 1755, ii, pp. 44–52; Collection complète des œuvres de C. Bonnet, 1779, ii, pp. 3–16.)

—— Mémoire sur la grande chenille à queue fourchue du saule, dans lequel on prouve, que la liqueur que cette chenille fait jaillir, est un véritable acide, et un acide très-actif. (Mém. math, de savants étrang., Paris, 1755, ii, pp. 267–282; Collection complète des œuvres de C. Bonnet, 1779, ii, pp. 17–24.)

Amoreux, P. J. Notice des insectes de la France, réputés venimeux, etc. Paris, 1789, pp. 282–285.

Schwarz, C. Neuer Raupenkalender. Nürenberg, 1791, Abth. i, p. 59.

Petzhold, C. P. Lepidopterologische Beyträge. (L. G. Scriba’s Beiträge zu der Insekten-geschichte, Frankfurt am Main, 1793, Heft 3, pp. 230–251.)

Nouvelle Dictionnaire d’Hist. Nat., xv, p. 487. (Larva of Hydrophilus ejects with a slight noise a fœtid and blackish fluid.)

Rengger, Johann Rudolph. Physiologische Untersuchungen über die thierische Haushaltung der Insecten. Tübingen, 1817. (In the chapter entitled Abgesonderte Säfte bei den Raupen, he speaks of the glandular apparatus of the larva of B. vinula, noticing the general form of the secretory sac, that it opens out in two muscular evertible points, out of which the secretion is ejected.)

Dufour, L. Mémoire anatomique sur une nouvelle espèce d’insecte du genre Brachinus. (Ann. de mus. d’histoire nat., xviii, 1811, pp. 70–81.)

—— Recherches anatomiques sur les carabiques et sur plusieurs autres coléoptères. (Ann. d. Sci. Nat., 1826, viii, pp. 5–54.)

—— Mémoire sur les métamorphosis et l’anatomie de la Pyrochroa coccinea. Glande odorifique. (Ibid., ii sér. Zoologie, xiii, 1840, pp. 340, 341.)

—— Recherches anatomiques sur les Diptères. 1851, pp. 195, 313. (Alimentary canal of Sepsis contains the seat of a “glande odorifique.”)

Kirby and Spence. Introduction to entomology, etc. (2d ed., i, 1815; London, 1818, ii, pp. 238, 239.)

Lyonet, P. Recherches sur l’anatomie et les metamorphoses de différentes espèces d’insectes. Ouvrage posthume. Paris, 1832.

Morren, C. Mémoire sur l’émigration du puceron du pêcher (Aphis persicæ), et sur les caractères et l’anatomie de cette espèce. (Ann. Sci. Natur. Zool., 1836, vi, pp. 65–93, Pls. 6, 7.)

Ratzeburg, J. T. C. Die Forstinsekten, etc. (Theil i, Die Käfer, etc., 1837, p. 246.)

Aubé, C. Note sur une sécrétion fétide d’Eumolpus pretiosus. (Ann. Soc. Ent. Fr., 1837, i, vi; Bull., p. 58.)

Lacordaire, J. S. Introduction à l’entomologie. 1838, ii, p. 45.

Meckel, von Hemsbach, Johann Friedrich. Mikrographie einiger Drüsenapparate der niederen Thiere. (Anat. Phys. u. wiss. Med., 1846, pp. 1–73, Taf. 1–3; p. 46, Müller’s Archiv.)

Stein, Friedrich. Vergleichende Anatomie und Physiologie der Insekten. Berlin, 1847.

Leidy, Joseph. History and anatomy of the hemipterous genus Belostoma. (Journ. Acad. Nat. Sci. Philadelphia, Ser. 2, 1847, i, Part i, pp. 57–67, Pl. 1.)

—— Odoriferous glands of invertebrata. (Proc. Acad. Philadelphia, 1849, iv, 234–236, 1 Pl.; Ann. and Mag. N. H., Ser. 2, 1850, v, pp. 154–156.)

Chapuis et Candèze. Catalogue des larves des coléoptères, etc. (Mém. Soc. Sci. de Liège, 1853, viii, pp. 351–653, Pls. 1–9, pp. 611, 612.)

Siebold, Carl Theodor. Lehrbuch der vergleichenden Anatomie der wirbellosen Thiere, 1848. (Burnett’s transl., Boston, 1854.)

Burnett, Waldo Irving. Translation of Siebold’s Anatomy of the Invertebrates, 1854. (Note on the osmeteria of Papilio asterias, which he regards as an odoriferous and defensive, rather than tactile, organ, p. 415.)

Karsten, H. Bemerkungen über einige shaarfe und brennende Absonderungen verschiedener Raupen. (Müller’s Archiv für Anat. Phys. u. wiss. Med., 1848, pp. 375–382, Taf. 11, 12.) Describes the poison-glands at the base of the spines of Saturnia larvæ.

—— Harnorgane des Brachinus complanatus. (Müller’s Archiv, 1848, pp. 367–376, Taf.)

Laboulbéne, Alexandre. Note sur les caroncules thoraciques du Malachius. (Annales de la Soc. Ent. de France, 3^e Sér., vi, 1858, pp. 521–528.)

Saussure, Henri de. Recherches zoologiques de l’Amerique centrale et du Mexique. (6^e Partie, Études sur les Myriopodes et les Insectes, Paris, 1860.)

Gerstaecker, C. E. A. Ueber das vorkommen von ausstülpbaren Hautanhängen am Hinterleibe an Schaben. (Archiv f. Naturgesch., 1861, xxi, pp. 107–115.)

Liegel, Hermann. Ueber den Ausstülpungsapparat von Malachius und verwandten Formen. Inaug. Diss., Göttingen, pp. 31, 1 Taf. (n. d., since 1858 and before 1878.)

Leydig, F. Zur Anatomie der Insecten. (Archiv f. Anat. Phys. u. wiss. Med., 1859, pp. 33–89, 149–183, Taf. 2–4, pp. 35 and 38.)

—— Ueber bombardier Käfer. (Biolog. Centralbl., x, 1890, pp. 395, 396.)

Claus, C. Ueber die Seitendrüsen der Larve von Chrysomela populi. (Zeits. f. wissens. Zool., xi, 1861, pp. 309–314, Taf. xxv.)

—— Ueber Schutzwassen der Raupen des Gabelschwanzes. (Würzburger Naturw. Zeitschrift, 1862, iii, xiv; Sitz. am., 28 Juni, 1862.)

Rogenhofer, Alois. Drei Schmetterlingsmetamorphosen. (Verhandlungen der k. k. zoolog.-bot. Gesellschaft, Wien, xiii, 1862, pp. 1224–1230.)

Fitch, Asa. Eighth report on the noxious and other insects of ... New York. (Trans. N. Y. State Agric. Soc., 1862, xxii, pp. 657–684), p. 677. (Separate.)

Guenée, Achille. D’une organe particulier que présente une chenille de Lycæna. (Annales Soc. Ent. de France, Sér. 4, 1867, pp. 665–668, Pl. 13.)

Landois, L. Anatomie der Bettwanze, Cimex lectularius, mit berücksichtigung verwandter Hemipterengeschlechter. (Zeitsch. f. wissens. Zool., 1868, xvii, pp. 206–224, 218–223, Taf. 11, 12.)

Studer, Theodor. Mittheilungen der naturforsch. Gesellschaft in Bern, 1872–1873, No. 792–811, p. 101.

Candèze, E. Les moyens d’attaque et de défense chez les insectes. (Bull. Acad. royale de Belgique, 2 Sér., xxxviii, 1874, pp. 787–816.)

Mayer, Paul. Anatomie von Pyrrhocoris apterus. (Reichert und du Bois-Reymond’s Archiv f. Anat. Phys., etc., 1874, pp. 313–347, 3 Taf.)

Scudder, Samuel Hubbard. Odoriferous glands in Phasmidæ. (Psyche, i, pp. 137–140, Jan. 14, 1876; Amer. Nat., x, p. 256, April, 1876.)

—— Prothoracic tubercles in butterfly caterpillars. (Psyche, i, pp. 64, 168, 1876.)

—— Organs found near the anus of the ♀ pupa of Danais, which recall the odoriferous organs mentioned by Burnett, transl. Siebold’s Comp. Anat. as occurring in Argynnis and other genera. (Psyche, iii, p. 278, 1882, p. 453, note 22.)

—— Glands and extensile organs of larvæ of blue butterflies. (Proc. Bos. Soc. Nat. Hist., xxxiii, pp. 357, 358, 1888.)

—— Butterflies of Eastern United States. i-iii, 1889.

—— New light on the formation of the abdominal pouch in Parnassius. (Trans. Ent. Soc. London for 1892, January, 1893, pp. 249–253.)

Müller, Fritz. Die Stinkkölbchen der weiblichen Maracujáfalter. (Zeitschr. f. wissens. Zool., 1877, xxx, pp. 167–170, Taf. 9.)

Plateau, Félix. Note sur une sécrétion propre aux coléoptères dytiscides. (Ann. Soc. Ent. Belg., 1876, v, xix, pp. 1–10.)

Edwards, William H. Notes on Lycæna pseudargiolus and its larval history. (Can. Ent., x, Jan., 1878, pp. 1–14. Fig.)

—— On the larvæ of Lycæna pseudargiolus and attendant ants. (Can. Ent., x, July, 1878, pp. 131–136.)

—— Butterflies of North America, i-iv. Many Pls. Phil., 1868—.

Voges, Ernst. Beiträge zur Kenntniss der Juliden. (Zeitsch. f. wissens. Zoologie, xxxi, p. 127, 1878. The scent-glands are retort-shaped bodies, the necks of which open into foramina repugnatoria.)

Rye, E. C. Secretion of water-beetles. (Ent. Month. Mag., xiv, 1877–1878, pp. 232, 233.)

Forel, A. Der Giftapparat und die anal Drüsen der Ameisen. (Zeits. f. wissens. Zool., 1878, xxx, Suppl., pp. 28–68, Taf. 3, 4.)

Saunders, William. Notes on the larva of Lycæna scudderi. (Can. Ent., x, Jan., 1878, p. 14.)

Weismann, A. Ueber Duftschuppen. (Zool. Anzeiger, 26th Aug., 1878, Jahrg., i, pp. 98, 99.)

Gissler, Carl Friedrich. On the repugnatorial glands in Eleodes. (Psyche, ii, Feb., 1879, pp. 209, 210.)

—— Odoriferous glands on the 5th abdominal segment in nymph of Lachnus strobi. (Fig. 273, p. 804, of Packard’s Report on Forest and Shade Tree Insects, 1890.)

Brunner von Wattenwyl, K. Ueber ein neues Organ bei den Acridiodeen. (Verhandl. k. k. Zool. Bot. Gesells. Wien., 1879, xxix; Sitzungsber., pp. 26, 27.)

—— Verhandl. k. k. Zool. Bot. Gesells. Wien. (A peculiar organ on hind femora of Acridiidæ.)

Rougement, P. Observations sur l’organe détonnant du Brachinus crepitans Oliv. (Bull. Soc. Sci. Nat. Neuchâtel, 1879, xi, pp. 471–478, Pl.)

Goossens, Th. Sur une organe entre la tête et la première paire de pattes de quelques chenilles. (Ann. Soc. Ent. France, ix, p. 4, 1809; Bull., pp. 60, 61.)

—— Des chenilles vésicantes. (Ann. Ent. Soc. France, vi, pp. 461–464, 1887.)

Coquillett, D. W. On the early stages of some moths. (Can. Ent., March, 1880, xii, pp. 43–46.)

Chambers, Victor Tousey. Notes upon some Tineid larvæ. (Psyche, iii, July, 1880, p. 67. Certain retractile processes “from the sides of certain segments of the larva.”)

—— Further notes on some Tineid larvæ. (Psyche, iii, p. 135, Feb. 12, 1881. Larva of Phyllocnistis has eight pairs of lateral pseudopodia on first eight abdominal segments.)

French, G. H. Larvæ of Cerura occidentalis Lint, and C. borealis Bd. (Can. Ent., July, 1881, xiii, pp. 144, 145.)

Passerini, N. Sopra i due tubercoli abdominali della larva della Porthesia chrysorrhœa. (Bull. Soc. Ent. Ital., 1881, xiii, pp. 293–296.)

Klemensiewicz, Stanislaus. Zur näheren Kenntniss der Hautdrüsen bei den Raupen und bei Malachius. (Verhandlungen d. Zool. Bot. Gesellsch. Wien., xxxii, pp. 459–474, 1882, 2 Taf.)

Weber, Max. Ueber eine Cyanwasserstoffsäure bereitende Drüse. (Archiv für Mikr. Anat., xxi, pp. 468–475, xxiv, 1882.)

Bertkau, Philip. Ueber den Stinkapparat von Lacon murinus L. (Archiv f. Naturg., 1882, Jahrg., xlviii, pp. 371–373.)

Dimmock, George. Organs, probably defensive in function, in the larva of Hyperchiria varia Walk. (Saturnia io Harris). (Psyche, iii, pp. 352, 353, Aug. 19, 1882. Account of lateral eversible glands on 1st and 7th abdominal segments; they emit neither moisture nor odor.)

—— On some glands which open externally on insects. (Psyche, iii, pp. 387–399, Jan. 15, 1883. Treats of poison-glands, glandular hairs, eversible glands of Cerura, etc.)

Coleman, N. Notes on Orgyia leucostigma. (Papilio, November-December, 1882, Jan., 1883, ii, pp. 164–166.)

Müller, F. Der Anhang am Hinterleibe der Acræa-weibchen. (Zool. Anzeiger, 6th Aug., 1883, Jahrg., vi, pp. 415, 416.)

Dewitz, H. Ueber das durch die Foramina repugnatoria entleerte Secret bei Glomeris. (Biol. Centralblatt, iv, pp. 202, 203, 1884.)

Williston, S. A. Protective secretion of Eleodes ejected from anal gland. (Psyche, iv, p. 168, May, 1884.)

Poulton, Edward Bagnall. Notes in 1885 upon lepidopterous larvæ and pupæ, including an account of the loss of weight in the freshly-formed lepidopterous pupæ. (Trans. Ent. Soc., London, June, 1886, pp. 156, 157, 159.)

—— Notes in 1886 upon lepidopterous larvæ, etc. (Trans. Ent. Soc., London, Sept., 1887, pp. 295–301.)

—— Notes in 1887 upon lepidopterous larvæ, etc. (Trans. Ent. Soc., London, 1888, p. 597.)

Künckel-d’Herculais, J. La punaise de lit et ses appareils odoriférants. (Comptes rendus, ciii, 1886, pp. 81–83; Annals & Mag. Nat. Hist., 5th Ser., xviii, 1886, pp. 167, 168.)

—— Étude comparée des appareils odorifiques dans les differents groupes d’Hemiptères hétéroptères. (Compt. rend. Acad. Sc., Paris, cxx, pp. 1002–1004.)

Packard, A. S. The fluid ejected by notodontian caterpillars. (Amer. Nat., 1886, xx, pp. 811, 812.)

—— An eversible “gland” in the larva of Orgyia. (Amer. Nat., 1886, xx, p. 814.)

—— Fifth Rep. U. S. Ent. Comm. Insects injurious to forest and shade trees, p. 136, 1890.

—— Hints on the evolution of the bristles, spines, and tubercles of certain caterpillars. (Proc. Boston Soc. Nat. Hist., xxiv, 1890, p. 551.)

—— Notes on some points in the external structure and phylogeny of lepidopterous larvæ. (Proc. Bost. Soc. Nat. Hist., xxv, 1890, pp. 83–114.)

—— A study of the transformations and anatomy of Lagoa crispata, a bombycine moth. (Proc. Amer. Phil. Soc., Philadelphia, xxxii, 1893, pp. 275–292, 7 Pls.)

—— The eversible repugnatorial scent glands of insects. (Journ., N. Y. Ent. Soc. iii, 1895, pp. 110–127; iv, p. 896; pp. 26–32, 1 Pl.)

Loman, J. C. C. Freies Jod als Drüsensecret. (Tijdschr. Neder. Dierk. Ver. Deel 1, 1887, pp. 106–108.)

Riley, Charles Valentine. Proc. Ent. Soc., Washington, March 13, 1888, i, pp. 87–89.

—— Notes on the eversible glands of larvæ of Orgyia and Parorgyia leucopæa and P. clintonii (achatina). (See 5th Rep. U. S. Ent. Comm., p. 137.)

Denham, Ch. S. The acid secretion of Notodonta concinna. (Insect Life, i, p. 147, 1888; hydrochloric acid.)

Michin, Edward A. Note on a new organ, and on the structure of the hypodermis, in Periplaneta orientalis. (Quart. Journ. Micros. Sc., Dec., 1888, xxiv, 1 Pl.)

—— Further observations on the dorsal gland in the abdomen of Periplaneta and its allies. (Zool. Anz., 27 Jan., 1890, pp. 41–44.)

Maynard, C. L. The defensive glands of a species of Phasma, Anisomorpha buprestoides. (Contributions to Science, i, April, 1889.)

Schaeffer, Cæsar. Beiträge zur Histologie der Insekten. (Zool. Jahrb. Morph. Abth. iii, pp. 611–652, Taf. xxix, xxx, 1889; treats of the ventral glands in prothorax of caterpillars; scales and hairs are secretions from the very greatly enlarged hypodermic cells.)

Gilson, G. Les glandes odorifères der Blaps mortisaga et de quelques autres espèces. (La Cellule, v. pp. 1–21, 1 Pl., 1889.)

—— The odoriferous apparatus of Blaps mortisaga. (Rep. 58th Meeting Brit. Assoc. Adv. Sc., 1889, pp. 727, 728.)

Haase, Erich. Ueber die Stinkdrüsen der Orthoptera. (Sitzgsber. Ges. Naturf. Freunde, Berlin, pp. 57, 58, 1889.)

—— Zur Anatomie der Blattiden. (Zool. Anz., xii Jahrg., pp. 169–172, 1889.)

Herbst, Curt. Anatomische Untersuchungen an Scutigera coleoptrata. Ein Beitrag zur vergleichenden Anatomie der Articulaten. Dissert., Jena, pp. 36 (Hautdrüsen, Coxal-Organ.); p. 1, 1889.

Wheeler, William M. Hydrocyanic acid secreted by Polydesmus virginiensis Drury. (Psyche, v, p. 422.)

—— New glands in the hemipterous embryo. (Amer. Nat., Feb. 1890, p. 187; odorous(?) glands.)

Jackson, W. Hatchett. Studies in the morphology of the Lepidoptera, Pt. i. (Trans. Linn. Soc., London, 2 Ser., Zoöl., v, May, 1890.)

Krauss, Hermann. Die Duftdrüse der Aphlebia bivittata Brullé (Blattidæ) von Teneriffa. (Zool. Anz., xiii Jahrg., 1890, pp. 584–587, 3 Figs.)

Fernald, H. T. Rectal glands in Coleoptera. (Amer. Nat., xxiv, pp. 100, 101, Pls. 4, 5, 1890.)

Verson, E. Hautdrüsen system bei Bombyciden (Seidenspinner). (Zool. Anzeiger, 1890, pp. 118–120.)

Vosseler, Julius. Die Stinkdrüsen der Forficuliden. (Arch. Mikr. Anat., xxxvi, 1890, pp. 565–578, Taf. 29.)

Carrière, J. Die Drüsen am ersten Hinterleibsringe der Insektenembryonen. (Biol. Centralblatt, xi, pp. 110–127, 1891.)

Borgert, Henry. Die Hautdrüsen der Tracheaten. Inaugural Diss., Jena, 1891, pp. 1–80.

Lang, Arnold. Lehrbuch der vergleichende Anatomie, English Trans. by Henry M. and Matilda Bernard, 1891, pp. 458, 459.

Kennel, J. von. Die Verwandtschaftverhältnisse der Arthropoden. (Schriften herausgegeben von der Naturforscher Gesellschaft bei der Universität Dorpat, vi, Dorpat, 1891.)

Patton, W. H. Scent-glands in the larva of Limacodes. (Can. Ent., xxiii, Feb. 1891, pp. 42, 43; eight pairs of glands with pores along the edges of the back.)

Batelli, Andrea. Di una particolarita nell integumento dell’ Aphrophora spumaria. (Monitore Zoöl. Ital. Anno 2, pp. 30–32, 1891. Dermal glands in the hindermost segment.)

Ash, C. D. Notes on the larva of Danima banksii Lewin. (Ent. Month. Mag., Sept. 1892, p. 232, Fig.) notodontian larva protrudes from under side of prothoracic segment a Y-shaped, red organ like that of Papilio; no odor or fluid given out.

Bernard, Henry M. An endeavor to show that the tracheæ of the Arthropoda arose from setiparous sacs. (Spengel’s Zool., Jahrbuch, 1892, pp. 511–524, 3 Figs.)

Latter, Oswald. The secretion of potassium hydroxide by Dicranura vinula, and the emergence of the imago from the cocoon. (Trans. Ent. Soc. London, 1892, 287, also xxxii; Prof. Meldola adds that the larva of D. vinula secretes strong, formic acid, and is the only animal known to secrete a strong, caustic alkali.)

—— Further notes on the secretion of potassium hydroxide by Dicranura vinula (imago), and similar phenomena in other Lepidoptera. (Trans. Ent. Soc. London; Nature, 1895, p. 551, March 20, 1895.)

Zograff, Nicolas. Note sur l’origine et les parentes des Arthropodes, principalement des Arthropodes trachèates. (Congrès Internationale de Zoologie, 2^e Session à Moscow, Aug. 1892; Part i, Moscow, 1892, pp. 278–302, 1892; cyanogenic glands in Myriopods, p. 287.)

Swale, H. Odor of Olophrum piceum. (Ent. Month. Mag., v, Jan. 1896, pp. 1, 2.)

Cuénot, L. Moyens de défense dans la série animale, Paris, n. d. (1892); the ejection of blood as a means of defence by some Coleoptera. (Comptes rendus, Acad. Sc. France, April 16; Nature, April 26, 1894.)

—— Sur la saignée réflexe et les moyens de défense de quelques insectes. (Arch. Zool. expér. (3), 1897, iv, pp. 655, 679, 680.)

Holmgren, Emil. Studier öfverhudens och de körtelartade hudorganens morfologi hos skandinaviska macrolepidopterlarver. (K. Svenska Vetenskaps-Akademiens Handlingar, xxvii, No. 4, Stockholm, 4º 1895, pp. 82, 9 Pls.)

Lutz, K. G. Das Blut der Coccinelliden. (Zool. Anzeiger, 1895, pp. 244–255, 1 Fig.)

Gilson, Gustav. Studies in insect morphology. (Proc. Linn. Soc. London, March 5, 1896; Nature, p. 500.)

—— On segmentally disposed thoracic glands in the larvæ of the Trichoptera. (Journ. Linn. Soc., London, xxv. 1897.)

Cholodkowsky, N. Entomotomische Miscellen, v, Ueber die Spritzapparate der Cimbiciden Larven, pp. 135–143, 2 Taf. Ibid., vi. Ueber das Bluten der Cimbiciden Larven, pp. 352–357, 1 Fig. (Horæ Soc. Ent. Rossicæ, xxx, 1897.)

Also the writings of Darwin, Wallace, Poulton, Weir, Beddard, Butler, Busgen, (pp. 365–367), Girard, Kolbe, Locy.

It is difficult to draw the line between repelling and alluring glands. Attention was first definitely called to the alluring odors of Lepidoptera by Fritz Müller, who showed that the males of certain butterflies are rendered attractive to the other sex by secreting odorous oils of the ether series. He pointed out that the seat of the odor is the androconia (see p. 199), while either repellent or pleasant odors are exhaled from abdominal glands.

Those of Pieris napi yield a scent like that of citrons, Didonis biblis gives off three different odors from different parts of the body, besides having a distinctly odorous spot on the hind wings. Both sexes have a sac between the fourth and fifth abdominal segments which exhales a very unpleasant (protective) odor, while the males have on the succeeding segment a pair of glands from which proceeds an agreeable odor like that of the heliotrope. Callidryas argante throws off a musky odor. In Prepona laertes the odor is like that of a bat, in Dircenna xantho it is vanilla-like, the androconia being situated on the front edge of the hind wings. In Papilio grayi the odor is said to be as agreeable and intense as in flowers. Certain sphingids are known to exhale a distinct odor, which Müller has traced to a tuft of hair-like scales at the base of the abdomen, and which fits into a groove in the first segment, so as to be ordinarily invisible.