401 



when at rest in both sexes). The body is fuller and plumper; abdomen less 

 acute at tip, and not spined as in A. vernata. It is uniformly ash-gray, with 



the anterior edge of the segments above (over which the segmenl in front 

 moves) mouse-colored. A row of five lateral dorsal black spols on the front 

 edge of each segment (sometimes wanting). On the side is a row of tine 

 black dots situated nearer the middle of the segment than the large subdorsal 

 spots. Antenna? and feet concolorous with the body. Beneath, colors as 

 above. Length of a gravid female, 0.40-0.42 inch. 



For further descriptions of the head and thorax of this and the female 

 A. vernata see the introduction, p. 38. 



Salem, Mass., October and November, on elm and apple trees; much 

 less common than A. vernata (Packard); Cambridge. Mass. (Harris, Mann. 

 Morrison); November 20, 1848 (Harris). 



Egg, larva, and pupa. — Egg cylindrical, increasing in diameter anteri- 

 orly, where it is truncated, being more rounded at the posterior end. On the 

 anterior end it is slightly convex, with a dark rim around the edge and a cen- 

 tral depression Length, 0.03 inch. On the 9th of April, 1875, tin' eggs of 

 this species were not developed, unless in a very early stage of the embryo. 

 The larva is pale whitish-green as a ground-color, with a broad, brown, 

 dorsal, median band and three lateral white lines, the middle of which is 

 fainter than the two others. These are succeeded by a broad, brown, spirac- 

 ular line, below which is a broad, continuous, white line. Body beneath flesh- 

 colored, without any median line. Head brown, with a whitish clypeal 

 region. Six abdominal legs reddish flesh-color or whitish ; the third smaller 

 pair, situated on the fifth abdominal ring, are one-half or one-third as large 

 as the adjoining ones, and are sometimes much smaller, while in two or three 

 out of the twenty-seven specimens examined this pair was nearly obsolete. 

 These specimens were gathered from several apple-trees, June' 15, in my 

 garden (Salem, Mass.). It varies a good deal, with a general tendency to 

 become darker, approaching in some cases remarkably near A. vernata Harris 

 in coloration, the brown lines being more prevalent, the light lines being finer 

 and slightly interrupted. 



There thus seems a decided tendency in the autumnal species to approach 

 Hie spring (vernata) ; and as the latter is the more abundant and wide-spread, 

 it is possible that autumnata is a derivation of vernata. As if in continua- 

 tion of this view, vernata, when it varies, becomes paler, and in some cases so 



51 P H 



