MOULTING OF CATERPILLARS. 171 



minute examination we found that it was impossible 

 for it to eat, as all its organs were in a state of 

 forward preparation for tiirowing off their exterior 

 coat, — the old skin, in fact, covering them as a glove 

 does the hand, and the new head lying distinctly 

 farther back than the old. jVeither the old man- 

 dibles therefore, which were become dry and stiff, 

 nor the new ones, which were encased in these, 

 could bite the leaves; and even if this had been 

 accomplished, the entrance to the gullet was ob- 

 structed by the shrivelling of the old skin there, 

 and deglutition could not have taken place. The 

 poor caterpillar was in consequence starved to death 

 in the midst of abundance of food, which it could 

 neither chew nor swallow. Had it been skilfully 

 assisted (as it was not) to get rid of the encum- 

 brance of its old skin, we doubt not that it might 

 ultimately have recovered.* Reaumur mentions the 

 very singular circumstance of a caterpillar of the 

 six-spot burnet moth {^Jlnthrocera Filipendulmy 

 Stephens) having actually, before its last moult, bit 

 off portions of its old skin, which it first raised up 

 and afterwards detached and tossed away. He did 

 not, however, ascertain whether this was an 

 accidental manoeuvre, or the usual process of this 

 species of caterpillar ;! though the first, we think, is 

 the more probable. 



The disorder called the Reds by the breeders of 

 silk-worms, shows itself in red-coloured stains and 

 blotches upon the skin; while the caterpillars seem 

 cramped, stupified, and suffocated, their rings dry up, 

 and they look exactly like mummies. Count Dando- 

 lo refers this and most other diseases of silk- worms to 

 chemical agency. The great quantity of vegetable 

 food devoured by caterpillars must be liable, during 

 hot weather to fermentation, if it be not digested 



* J. R. i" R'^umur, Mem. ii, 75. 



