STATES OF INSECTS. 223 



glued to each other, as to separate with facility ; but in 

 that of the emperor-moth just mentioned they are inti- 

 mately connected by a gummy matter, furnished, as 

 Reaumur conjectures, from the anus a , with which the 

 whole interior of the cocoon is often plastered. Some, 

 as that of the silk-worm, are composed of an exterior 

 loose envelope, and an inner compact ball ; others have 

 no exterior covering, the whole cocoon being of an uni- 

 form and thick texture. The larva of Cossus Robinice 

 Peck, in spinning its cocoon, makes the end next the 

 opening to the air, by which the imago is to emerge, of a 

 slighter texture than the rest of it b . The exterior case 

 is sometimes, as in Laria pudibunda, very closely woven, 

 so as to resemble a real cocoon c : its form is usually 

 adapted to that of the inner one ; but in some which fix 

 them under flat surfaces (Laria fascelhia, Callimorpha 

 Cqja,) it resembles a hammock d . Cocoons of a close 

 texture have generally no orifice in any part ; but that of 

 Eriogaster lanestris is spun with openings, as if bored 

 from without, the use of which, however, does not seem 

 to have been ascertained e . 



Many silken cocoons are of so close a fabric, as, when 

 finished, entirely to conceal the included insect; but a 

 very considerable number are of a more open texture, 

 composed of a much smaller quantity of silk, and that 

 woven so loosely, that the larva or pupa may always be 

 discovered through it. Of this description are the co- 

 coons of Hypogymna dispar, Arctia Saltcis, &c, which 

 consist only of a few slight meshes. Those of some others 



* Reaum. i. 503. b Peck on Locust-tree Insects, 69. 



c Bonnet ii. 260. d Sepp. iv. t.ii.f. 4. 



e Brahm. Ins. Kal. 289. 



