216 INSECTS OF MASSACHUSETTS. 



it in so many respects, that I do not hesitate to give it another 

 name, and will therefore call it the hop-vine Thecla, Thecla Hu- 

 muli.* The wings on the upper side are dusky brown, with a 

 tint of blue gray, and, in the males, there is an oval darker spot 

 near the front edge ; the hind-wings have two short, thread-like 

 tails, the inner one the longest, and tipped with white ; along the 

 hind-margin of these same wings is a row of little pale blue spots, 

 interrupted by a large orange-red crescent enclosing a small black 

 spot ; the wings beneath are slate-gray, with two wavy streaks of 

 brown edged on one side with white, and on the hind-wings an 

 orange colored spot near the hind-angle, and a larger spot of the 

 same color enclosing a black dot just before the tails. It expands 

 one inch and one tenth. 



Some butterflies have the first pair of legs so much shorter 

 than the others, that they cannot be used in walking, and are 

 folded on the breast like a tippet. Their caterpillars, when about 

 to transform, do not make a loop to support the forepart of the 

 body, but suspend themselves vertically by the hindmost feet. 

 As they all secure themselves pretty much in the same way, it 

 may be proper to explain the process. Having finished eating, 

 the caterpillar wanders about till it has discovered a suitable situa- 

 tion in which to pass through its transformations. This may be 

 the under-side of a branch or of a leaf, or any other horizontal 

 object beneath which it can find sufficient room for its future oper- 

 ations. Here it spins a web or tuft of silk, fastening it securely 

 to the surface beneath which it is resting, entangles the hooks of 

 its hindmost feet among the threads, and then contracts its body 

 and lets itself drop so as to hang suspended by the hind-feet alone, 

 the head and forepart of the body being curved upwards in the 

 form of a hook. After some hours, the skin over the bent part of 

 the body is rent, the forepart of the chrysalis protrudes from the 

 fissure, and, by a wriggling kind of motion, the caterpillar-skin is 

 slipped backwards till only the extremity of the chrysalis remains 

 attached to it. The chrysalis has now to release itself entirely 

 from the caterpillar-skin, which is gathered in folds around its tail, 



• M. Boisduval has figured anil described this species under the name of Thecla 

 Favoni.us, in his " Histoirc des Lcpidopteres de rAinc'rique Septentrionale.'' 



