PAPILIONINAE : EUPHOEADES TROILUS. 1323 



neiglihoring leaves, very rarely upou that it has selected tor its abode. 

 A\'lH'n this has become too strait for its rapidly growing body, it forms 

 another of similar nature but of larger size, the edge falling upon or 

 beyond the midrib (82:4) ; and finally, in its last stage or even earlier, it 

 takes up its position upon the very midrib and by the same process causes 

 the opposite edges of the leaf to exactly or almost exactly meet above its 

 back, leaving only a passage out, and often a very confined one, next the 

 leafstalk (.82: G). Thus it passes its entire larval life, when not feeding 

 or pre[)aring its abode, in entire concealment, undergoing all its ecdyses 

 within the cleanly home, where it drops no excrement and suffers none of 

 its cast off clothing to remain, eating up its cast off skin and hustling its 

 no-longer-needed skull-cap out uj)on the ground. 



The ordinary movements of the full grown larva when exposed to view have 

 an absurdly affected look. It moves or seems to glide by little starts about 

 a second apart, in a very slow and measured way. It is evidently no neces- 

 sity of its organization, but a superinduced habit for some protective pur- 

 pose, probably in correllation with its great thoracic spots and hunch. 

 Probably this panting spasmodic approach of so singular looking an object 

 may be a source of fright, possibly of curiosity, to some of its natural 

 enemies, sufficient to protect it until it again gains cover. 



Owing to its "musky" odor. Abbot says this caterpillar has gained in 

 the south the name of "mellow bug"; yet it seems to be less inclined to 

 use its osmateria than our other Papilioninae, and when provoked to do 

 so generally ejects them but partially, even when full grown ; in the first 

 stace it cannot with the roughest handling be induced to use them. 



The color of the caterpillar is exactly that of the leaf on which it rests. 

 One or two days before changing to chrysalis the caterpillar, like others 

 of the group, ejects the entire contents of the alimentary canal, reducing 

 the animal very materially in size ; shortly afterward its color undergoes a 

 decided alteration, the green changing to yellow*, closely resembling, as 

 Miss Guild pointed out to me, the appearance of the sassafras leaf after a 

 frost. So, too, the color of the chrysalis is usually that of the dead sassa- 

 fras leaf. 



Pupation. ^Ir. C. V. Riley sends me the following account of the 

 caterpillar's preparation for its change : — 



After attaching the anal prolegs it forms its loop, not, as is generally supposed, by 

 turning the head entirely baclc with the mouth parts opposing the object attached to, 

 but by carrying the silk between the first and second pair of thoracic legs. With the 

 prolegs fastened flrmly to the vertical side of ray cage, the whole operation was per- 

 formed with the five anterior segments of the body. After attaching one end of the 

 future loop it stretched back as far as those Ave segments would allow, they being 

 horizontal or at right angles with the other seven. In this position the head is bent 



• The spots, however, remarks Riley, change which remains black to the end of its life, 

 to a slate color, excepting the eye-like spot 



