336 THE BUTTERFLIES OF NEW ENGLAND. 



Dimorphic forms. The following peculiarities distin.a;iiisli the form dryas from 

 liarrisii, which served as tlie basis of the foregoing description : First, as regards form, 

 the fore wings have the upper portion of the outer l)order slightly concave, the denta- 

 tion nearly rectangular, that at tip of lower median nervule slight and broadly 

 rounded; outer margin slightly crenulate. The hind wings (61:1!)) have the outer 

 border scarcely crenulate, the tail of the upper median scarcely longer than broad, 

 scarcely tapering ; the projection at the tip of the upper subcostal slight, angulated, 

 that at the lower angle very small, rounded. 



The coloration of the upper surface does not difier from the form harrisii, except in 

 the consideral)le infuscation of the apical half of the hind Avings, which is generally 

 more intense and extensive in the $ than in the $ , and by which the submarginal 

 series of fulvous spots are obscured or very nearly obliterated, and the basal, blackish 

 markings of the median interspaces blended with the rest ; but the other black mark- 

 ings near the upper half of the middle of the wing remain nearly or quite as distinct 

 as before. Beneath, the J difters almost too little from the $ of the form harrisii to 

 merit notice, the yellow tints generally prevailing here and the brown there ; the $ 

 however, is quite distinct ; the distinction in tone between the basal and apical halves 

 is almost lost, and the general tint is a nearly uniform brownish, someAvhat smoky, 

 yellow; in the foi-e xoings faint traces of the intraraesial band remain, especially 

 toAvard either border, and the spots in the cell are represented by their bordering lines ; 

 but the apical cloud avouUI hardly be noticed but by a comparison Avith the other form, 

 and the whole apical half of the Aving, excepting the outer border, is nearly uniform 

 in color, liberally streaked Avith short transverse threads of pale ferruginous scales. 

 The transverse series of dots is more distinct than in harrisii, and just Avithin its upper 

 extremity is a slight, transverse, AA'hitish, tapering bar depending from the costal bor- 

 der ; the outer border is marked much as in the $ but rather less distinctly. The hind 

 wings preserve the general character of the fore Avings, but the row of dots is en- 

 closed in a common band of slightly fuscous ferruginous, and within it the apical half 

 of the Aving is faintly tinged Avith a lilaceous bloom, Avliich sometimes also borders it 

 externally; the outer border resembles that of the $ very closely, difl'ering from it 

 only as the fore Aving does from the fore Aving of the $ . 



Egg (64: 18). Short blunt OA'ate in shape, broadly rounded beneath, alcove a little 

 flattened, broadest in the middle of the loAver tAvo-thirds, Avith eleven strongly com- 

 pressed vertical ribs Avliich increase in height from base to summit, more rapidly 

 above; surface betAveen them scarcely concave, smooth, crossed by exceedingly fine 

 lines, which traverse also the ribs and make them appear striate. The ribs are 

 about .06 mm. high at the top, but only one-third of that in the middle of the 

 egg; they are about .22 mm. apart, and the cross lines .02 mm. apart. Color of egg 

 pale green, glistening, the ribs pale. The termination of the ribs above leaves a free 

 central space .17 mm. in diameter. Micropyle rosette .0G5 mm. in diameter, made up of 

 a cluster of nearly equal hexagonal cells, about .01 mm. in diameter. Height of egg, .8 

 mm. ; Avidth at greatest, .7 mm. ; at summit, .4 mm. 



Caterpillar. First stage. Head piceous. Body above varying Avith age from a pale 

 straw color to a dull rather dark green, the anterior portions of the segments livid, 

 but Avith the last tAvo segments A^arying from light to purplish broAvn ; beneath yelloAvish 

 green. Papillae and hairs (86 : 67) black. Legs and prologs dusky. Length 2. 75 

 mm. 



Second stage. Head dark broAvn [probably piceous]. Body brown-black or black, 

 Avith Avhitish lines at the incisures. Spines black, arising from papillae Avhich are 

 black, or, in those Avith Avhite lines, Avhite on the tlurd thoracic and second, fourth, 

 and sixth abdominal segments ; hairs l)lack. Legs black; prologs olivaceous. Length, 

 3.3 mm. (After EdAvards.) 



Third stage. Head piceous, most of the papillae black, the others Avhite, the hairs 

 pellucid or dusky. Body reddish brown, heavily traversed by transverse dusky lines, 

 becoming blackish next the base of the spines ; the inf rastigmatal fold sometimes a 

 little pale. Spines black, excepting the laterodorsal series on the fourth and sixth 



