78 Annals Entomological Society of America [Vol. XI, 



to the fifth last abdominal segment. All this time the mandibles 

 of the larva have remained fixed, but when the last five segments 

 have renewed contact with the leaf, the head is slowly raised. 

 The anterior region of the body may be moved slowly from 

 side to side, finally extending straight forward, eliminating the 

 arch of the inverted U. The whole body then comes to rest on 

 the leaf. The final result of this methodical series of movements 

 is that the animal has now advanced in its progression just as 

 far as the distance measured by the last body-segment in its 

 original displacement. The whole process is marked by the 

 extreme slowness of an orderly series of individual reflex, actions 

 which impart to the observer the notion of an apparent calcu- 

 lation on the part of the organism by reason of their perfect 

 co-ordination. The persistence of the appropriate stimuli 

 determines the continued repetition of the whole series of 

 ambulatory reactions. 



In a quiescent condition, the thoracic region of the body has 

 a noticeably humped appearance, apparently produced by the 

 slight ventral retraction of the head-segment. 



The full-grown larvae are very sluggish and inactive. When 

 disturbed, they relax their hold on the leaf -surf ace and readily 

 fall to the ground. This response to a disturbing factor, together 

 with their marked resemblance to the leaf-color, appears to be 

 their only asset of defense against ^predaceous species. In all, 

 somewhat more than one hundred adults were reared from 

 larvae collected in the field, and in not a single instance was one 

 found to be parasitised. 



Pupation. — Previous to pupating, the larva attaches itself 

 firmly to the surface of the leaf or leaf-petiole by means 

 of its anal pseudopodia. The skin splits transversely posterior 

 to the head but is only partially sloughed off. The head, thorax 

 and first four abdominal segments of the pupa are exposed, but 

 the remainder of the abdomen remains enclosed in the larval 

 skin, the terminal portion of which, attached to the leaf-surface, 

 is collapsed and wrinkled. The head-capsule of the larva which 

 is moulted with the rest of the exuvium, lies ventrad of the 

 fifth abdominal segment of the pupas. On the leaf, pupation 

 may take place on both the upper or lower surfaces, but gen- 

 erally on the former. On the petiole, the pupae generally occur 

 at the axils. 



