Mar. 7890.] DVAR : LiFE HISTORIES OF N. Y. SlUG CATERPILLARS. 63 



gence takes place late in the afternoon or early evening, flight 

 occurs early, pairing the same night and the eggs begin to be 

 laid the following night. They are placed singly or in small 

 groups on the under sides of the leaves. The larvae are found usually 

 several on the same plant on low shrubs or the lower limbs of trees of 

 their food plants. The first stage may be found rarely as late as the 

 first of August, and the first mature larvae early in September. There 

 is but a single brood in the year. The larvae rest on the under sides 

 of the leaves, colored green, without conspicious marks. The sting- 

 ing power of the spines is not great, and the subdorsal ones are bent 

 down outwardly at maturity when not in use. There are eight larval 

 stages, occasionally but seven by the omission of the normal stage III. 

 The sexes have different attitudes of rest. The 9 moth sits with 

 the body bent over the back, the wings closed beneath it and parallel 

 to the twig, as is usual. The S sits in the reverse position, the head 

 hanging down, the body enclosed by the wings of which only the tips 

 touch the twig. It holds loosely by the middle legs, which are partly 

 extended, the other pairs being folded up. In this position the white 

 dots at the bases of the forelegs and bases of antennae are quite con- 

 spicuous. The 9 does not exhibit the white dots, though possessing 

 them. 



Criticism of Previous Descriptions. 

 Glover gives a recognizable figure of the larva, life-size, but with- 

 out identification. I have myself briefly referred to some of the char- 

 acters in comparison with certain Australian forms. 



Description of the Several Stages in Detail. 



£gg. Elliptical, flat, very large, translucent whitish, shining ; 

 reticulations distinct, linear, irregularly quadrangular. Size, 2xi.6x 

 . I mm. 



Stage I. (Plate I, fig. i.) Head whitish, eye black; body el- 

 liptical, dorsal space broadest anteriorly, not narrower centrally ; seg- 

 ments fairly well marked ; skin smooth. A subdorsal and a lateral 

 row of thick, horn-like prominences, eleven in the subdorsal row 

 (joints 3 to 13), nine in the lateral row (joints 3, 4, 6 to 12); the 

 subdorsals of joints 3, 4 and 13 large, well developed, of the structure 

 of Sisyrosea textula, an apical seta and radiating crown around it, all 

 with enlarged tips (Plate I, fig. 3). The central subdorsals, as well 



