1406 Tin-: BUTTERFLIES OF NEAV ENGLAND. 



that the under surface of the fragment is uppermost ; this roof is kept in 

 place by long silken strands attached to the edges of the fragment and the 

 surface of the leaf heyond, in such a way as to arch tiie roof, like a dome ; 

 the pieces cut in this manner are irregular in form, and vary from 5 to 13 

 mm. in diameter; the edges of the roof are from 2 to 5.5 mm. above the 

 leaf. AVhen older it attaclies two leaves in a similar manner, fluting the 

 edges by attaching to them silken cords at short distances so as to dome 

 the upper leaf considerably (82:11). In this way tliese caterpillars, says 

 Harris (Ins. Inj. Veg., 311-312), 



form a kind of cocoou or leafy case to shelter them from the weather, aud to screen 

 them from the prying eyes of birds; although there maybe aud often are, many of 

 these caterpillars on the same tree and branch, yet they all live separately within their 

 own cases. One end of the leafy case is left open and from tliis the insect comes 

 forth to feed. They eat only or mostly in the night and Iceep themselves closely con- 

 cealed by day. These caterpillars are very cleanly in their habits aud malieno dirt in 

 their Ual)itation, l)ut tlirow it out with a sudden jerk so that it sliall fall to a consid- 

 erable distance [often several yards]. . . . The viscid locust tree is sometimes almost 

 completely stripped of its leaves by these insects, or presents only here and there the 

 brown and withered remains of foliage which has served as a temporary shelter to 

 the caterpillar. 



Abbot says that sometimes " for greater safety from birds" ( ?) the nest 

 is made in the leaves of another plant in close proximity. 



In a single night, one nearly full fed caterpillar placed among fresh 

 leaves spun silk, apparently in a vain effort to construct a nest, over a 

 dozen or more leaves, and extended threads from one point to another, one 

 of which was 32 mm. long and very strong; but besides all this work it 

 ate large pieces out of six different leaves, devouring even the ribs — in 

 all a quantity equal to two leaflets of the common locust. The caterpillar 

 when disturbed moves its head from side to side with spasmodic starts, its 

 black jaws wide open aud sua^tping at e^erj-thing brought into contact 

 with them. After moulting it devours the cast off pellicle, excepting the 

 head-shell. I have never foimd it feeding except at night. 



I formerly stated that the caterpillar had a musky odor ; but discovered 

 later that the odor supposed to have come from them came from some half 

 dried Gleditschia leaves in the box where they were feeding. Reed states 

 that the deserted nests of the caterpillar are sometimes used as hiding 

 places by the beetle, Cyllene pictus, which seem "to enjoj' the cool 

 retreat thus provided for them from the heat of the sun." Mrs. Mary 

 Treat says that while Formica sanguinea, in common with other ants, 

 greedily seeks for the caterpillar of Eurymus and carries many to its nest, 

 " all species of ants turned away . . . apparently in great disgust," from 

 caterpillars of tityrus offered to them. 



Cocoon and pupation (86: 20; 87: 12). Harris remarks in his 

 account of this insect (loc. cit.) that "they frequently transform to chry- 

 salis within the same leaves which have served them for a habitation, but 



