PLATE 27. Insects. 



Figure 



1 . Gizzard of cricket (Acheta domestica) . 



20. Under membrane of elytrum of cockchafer (Melolontha vulgaris) ; 2 b, se- 

 parate hair or spiniform papilla (ELYTRA). 



3. Scale of Lepisma saccharina, in liquid ; showing air-bubbles imprisoned by the 



longitudinal ridges. 



4. Hind leg of neuter honey-bee (Apis mellifca), with pollen-brushes on the first 



joint of tarsus a ; c, tibia ; d, femur ; e, trochanter ; 4 b, outside of tibia 

 hollowed out. 



5. Leg of middle pair of Gyrinusnatator. a, tarsus; c, tibia; d, femur; e, trochanter. 



6. Anterior leg of male Dytiscus marginalia, a, tarsus, the first three joints with 



the suckers ; b, one of the smaller ones more magnified ; c, tibia. 



7. Leg of fly (Musca domestica) . a, tarsus ; c, tibia ; d, femur ; e, trochanter. 



8. Tar sal pulvillus of blow-fly, with hair-like suckers. 



9. One of the hair-like suckers of the same, more magnified. 



10. Anterior wing of male cricket (Acheta domestica). a, drum; b, file (fig. 12, 



the file more magnified). 



11. Anterior wing of humble-bee (Bombus terrestris). n, fold over which the hooks 



of the posterior wing play. (See INSECTS, wings, and WINGS.) 



12. File of cricket (compare fig. 10 b). 



13. Costal nerve of hind wing of humble-bee (Bombus terrestris), with the hooks. 



(See INSECTS, wings.) 



14. Sting and poison apparatus of mason-bee (Anthophora retusa). a, b, sheath of 



sting ; c, reservoir ; d, duct ; e,f, secretory organs. 



15. Single sting of wasp (Vespa vulgaris). 



16. Spinning organs of silkworm (Bombyx mori). 



1 7. Trachea of a caterpillar ; lower part of the branch containing air. 



18. Internal reproductive organs of male mole-cricket (Gryllotalpa vulgaris) . a, testes; 



b, vasa deferentia ; c, c', prostate (blind tubes) ; d, root of penis, with caeca 

 (Cowper's glands) at the upper part. 



19. Female organs of the same, a, a, ovaries; b, b, oviducts; c, receptacle of 

 semen (blind sac), the very slender tube of which c' opens into the vagina d. 



20. Battledore scale of Polyommatus argiolus, dry ; 20 , a portion immersed in 



water, and more magnified. 



21. A scale of the same seen in Canada balsam. 



22. Scale from the wing of the gnat (Culex pipiens). 



23a. Scale from the wing of male Pontia rapce, dry; 23 b, portion of wing of the 

 same, showing the attachments of the two kinds of scales, a and b. 



24. Scale from wing of male Pontia brassicce, dry. 



25. Scale from under side of wing of clothes-moth (Tinea vestianella) . 



26. Portion of wing of Pontia brassicce, dry, showing the imbricated arrangement 



of the scales, and the wrinkling of the epidermis at their insertions. 



27. Hair-like scales from clothes-moth, dry. 



28. Scale from wing of Lasiocampa quercus, dry; 286, upper portion of the 

 same, more magnified, dry. 29. Scale from wing of Papilio Paris, dry. 



30. Scale from larva of Attagenus pellio, dry. 



31. Portion of the above, more magnified. 



32. End of one of the posterior legs of the larva of a Sphinx. 



33. Anterior leg of the same. 



34. Spiracle of Dytiscus marginalis; the appended figure represents one of the 



marginal processes more magnified. 



35. Portion of outer membrane of the ovum of the blow- fly (Musca vomitoria). 



