GRAPTA II. 



laterals, on Sth to 11th segment inclusive, appears a ferruginous jDoint. With very 

 little change this type reaches maturity. Other larvie are almost wholly hlack to 

 maturity, wanting the dorsal ami lateral green spots and showing merely transverse 

 striie on each segment. Others are hlack while young, hut when one-third grown 

 become greenish white with faint shades of black interspersed as if seen though a 

 semi-transparent skin. And others again are like the last mentioned but have a 

 reddish or vinous tint instead of blaclc. I have not been able to discover that the 

 variation of the larvse has any connection with the sex or with the shades of color 

 of the butterfly. 



The lenoth of the mature larva is 1.25 inch. When about to transform it 

 selects a convenient place, on the under side of a projecting rock, or of a fence 

 rail, or of a weather board of the house, or the midrib of a hoi>leaf, and having 

 spun a little button of pale red silk fixes the hooks of its anal legs therein and 

 hangs suspended, head downwards, in the shape of a fish-hook, and immoveable, 

 for the space of twenty to twenty-four hours, no change being perce^jtible except 

 in the color of the skin wliich becomes jiartly transparent and loses its dark color, 

 owing to its gradual parting from the chrysalis witliin. Suddenly, and to a looker 

 on without any jiremonitory symj^tom, a rent takes i)lace in the skin at the back 

 of the head just wide enough to allow the ])assagfe of the chrysahs, the head of 

 which at once emerges. By a ra])id contraction and expansion of the folds of the 

 abdomen the larva draws the skin upwards successively discovering the parts of 

 the fully formed chrysalis, until at last, and in scarcely more than one minute of 

 time, the entire skin is gathered about the anal feet. It now bends itself violently to 

 disengage the end of the chrysalis, which is long, j^ointed and hard, furnished with 

 several little hooks, meanwhile retaining its' hold of the skin by the folds of its ab- 

 domen, until after a severe eftbrt convulsively reaching out and feeling in all direc- 

 tions for the object of its search, it touches the button of silk and at once grasps it 

 with its hooks and fixes them in it securely. Then by a twisting motion it man- 

 ages to disengage the loose skin, which falls to the ground, and the chrysalis rests. 

 The whole process is most interesting to witness and excites renewed wonder with 

 every repetition, at the ingenuity of the means employed and the delicacy of the 

 instinct displayed. How to strip off the skin and much more the legs by which 

 the creature is susijended, without losing its hold, and at same time to securely 

 fasten the chrysalis, is a problem that would seem im[K)ssible to solve, and yet this 

 little insect accomplishes it unerringly, when to fail Avould be certain destruction. 

 And not this species only, but the larvae of all butterflies which form susj^ended 

 chrysalids, embracing the whole of the great family of Xymphalida;, that is, a large 

 proportion of all existing species of butterflies, undergo a similar transformation. 



The chrysalis is now green in color, soft and indefensible, susceptible to the 



