EXPLANATION OF THE PLATES. 605 



FIG. 



1 6. a. w. Specimens of scales from the wings of various Le- 

 pidoptera. (Reaum., De Geer.) VOL. III. p. 644. 



PLATE XXIIL 



1. One of the prolegs of a caterpillar. Cossus. (Lyonet.) 



a. Its coronet of spines. VOL. III. p. 134. 



2. One of the spiracles of ditto. (Ibid.) VOL. IV. p. 37. 



3. Three of the hexagonal lenses of a bee's eye, with their 



prisms. (Swamm.) VOL. III. p. 496. 



4. Trunk of a flea with the head removed, showing that all 



the legs are attached to the former. Ibid. p. 656. 



5. Alitrunk of Dytiscus marginalis, exhibiting the wings as 



they are folded when unemployed. 



6. Part of ditto, with the scutellum and apex of an elytrum, 



to show the alula. VOL. II. p. 343 j III. 557, 



7. Anterior and posterior prolegs of Tanypus maculatus. 



(De Geer.) a. Posterior proleg. 6. Anterior ditto. 

 VOL.. II. p. 275; IV. p. 363. 



8. Posterior extremity of a pupa, to show the cremaslrce, or 



hooks by which it is suspended, a. Hooks. VOL. III. 

 p. 209, 255 ; IV. p. 363. 



9. Another specimen, in which the hooks are more numerous, 



a. Hooks. 



10. Pulex penetrans, or the Chigoe. VOL. I. p. 49, 102. 



1 1 . Mandible of the larva of Myrmeleon Formicaleo. (Reaum.) 



VOL. III. p. 121. 



12. Anal spinneret of ditto. (Ibid.) 



13. Branching palpus, or feeler of Trombidium holosericeum. 



14. Part of the tarsus of a spider, to show the simple and pec- 



tinated claws. (De Geer.) VOL. III. p. 690. 



15. A pair of spinners of a spider. (Leeuwenh.) VOL. III. 



p. 392. 



1 6. A marnmula or teat of ditto. VOL. III. p. 39 1 . 



17. Anus of ditto. 



18. Stilt-legs of a dipterous larva. (DeGeer.) 



