466 THE BUTTERFLIES OF NEW ENGLAND. 



own, the young caterpillar, not a day out of the egg, constructs a dense 

 white mat, beneath which upon the clean surface of the leaf it takes up its 

 abode. This mat resembles closely in the spring the central vuifolded 

 leaves of the Gnaphalium and also the silken cocoons of the lesser ichneu- 

 mon flies, and is so dense that not the slightest view of the interior can be 

 gained. Beneath this the caterpillar devours the parenchyma of the leaf 

 through to the under pellicle, and when it has devoured all that it can 

 reach it constructs a new nest, this time usually by folding together to a 

 greater or less extent two adjoining leaves, and thereafter makes not in- 

 frequent changes of abode, probably quite as many in the course of its life 

 as its changes of skin, though they do not appear to be coincident in any 

 way with ecdysis. When the plants are still young and scarcely elevated 

 above the ground, the half grown caterpillar will sometimes construct a 

 nest beneath the leaves and in part directly upon the ground. So far as 

 I have observed, tliey do not then leave their nests for food, bvit feed ap- 

 parently only upon the portions enclosed within their web. In the autumn, 

 wdien the flowers of everlasting are fairly opened, they almost invariably 

 enclose them within their web, and pick these blossoms to pieces until, as 

 Mr. Emery writes me, "they resemble cotton, apj^arently devouring the 

 centre or kernel and making a nest with the husks connected by a slight 

 web (81 : 11). This gives the naturally flat summit of the plant a rounded 

 appearance. Only one is found on a plant." Mr. Saunders says (Can. 

 ent., i: 105-106) of one of these caterpillars, "It had drawn the leaves 

 too-ether and fastened them into a rude case with silken threads. The 

 larva during its growth had consumed portions of the inner surface of the 

 leaves, especially near their summit, and hence, here the foliage was 

 crisp and blanched. These whitened portions of the leaves, together w4th 

 the size of the case occupied by the larva when full grown, enables the 

 collector readily to discover their places of retreat." Mr. Riley also writes 

 me that the larva "feeds on the parenchyma, leaving the glistening white 

 leaf-membrane untouched" ; and this I have myself observed even in the full 

 grown caterpillar, which feeds outside its web as well as beneath it ; though 

 in the last two or three days of its life it devours the whole thickness of 

 the leaf, and cares far less for concealment, though never so conspicuous 

 and gaily colored as now. 



The excrement of the full grown caterpillar is very large, forming rude 

 cylindrical pellets 2,25 mm. in diameter and 3.5 mm. long when dry. 

 The caterpillar grows rapidly at first, but more slowly than usual after- 

 wards. Mr. F. H. Sprague calls my attention to the curious fact that the 

 very young caterpillars often assume a sphinx-like attitude. I am indebted 

 to Miss Guild and to Messrs. Saunders, Emery, Stebbins, F. H. Sprague, 

 Beadle and others for living specimens of this insect in its earlier 

 stages. 



