MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 213 



Moth. — Three A , five 9 . Head ash, tawny ashen, with reddish brown discolorations, thorax 

 ash color with reddish brown scales behind. Fore wings very i»ale tawny in the middle of the 

 wing-, between the cinereons costa and the brown inner margin. No transverse lines. At the 

 base along the cnbital vein is a dark streak; there are three dark spots on the costoapical region; 

 another faint linear niinnte streak in the apical interspace; in tlie two spaces below are two faint, 

 long, linear slight lines between the dark veunles. A minute but distinct discal dot succeeded by a 

 linear streak reaching to the outer margin. Near the internal angle are two unequal linear spots. 

 A faint row of marginal brown lunules. Near the internal angle is a brown geminate discoloration. 

 Hintl wings in i wliite with a dusky discoloration on the inner angle. Wings beneath pale; fore 

 wings a little dusky externally; the three costo-apical dots and the spotted fringe visible beneath. 

 Fringe brown on the venules. 



Female: Baseof the fore wings fuscous; beyond ashy; a distinct submedian dark basal streak, 

 a minute discal dot, with a faint brown strealc beyond. Two twin costoapical streaks, more distinct 

 than in the S , so also two larger, broader spots near the intei-nal angle. The marginal row of 

 spots more distinct. Hind wings dark, ashy, reddish brown. 



Expanse of wings, S -'SO mm., 9 30-31 mm.; length of body, S 10 mm., 9 17 mm. 



It differs from badia in tlie wings being narrower and longer; the base of the fore wings is less 

 reddish, routider, not lunate. The fringe is whiter on the edge; there is no reddish tinge on the 

 liind wings. It is a slender species. After a careful examination I am unable to perceive any 

 difference between what I have decided to be nit Ida and this species. This species, like the rest of 

 the genus, is remarkable for the difference in the cohjr of the hind wings in the two sexes. 



A $ in the United States National Museum, labeled "240 L, from Coeur d'Alene City, 

 Idaho, August 29, 1891," is, though rubbed, evidently paler on the fore wings, with less reddish 

 brown than the Eastern individuals. There is no doubt about the species, as the basal 

 longitudinal reddish sti'ipe is present, and it does not differ materially otherwise. It is no larger, 

 tlie alar expanse being 30 mm. 



Var. salicis Edw. (one S . Type, California. I also have a S given me some years since by Mr. 

 Edwards). I can not, after repeated examination, really perceive any difference between this and 

 the Eastern concinna; it only differs in size, being a little larger and with slightly more pointed 

 fore wings, as one would expect to lind it, in accordance with the facts pointed out in my 

 Monograph of Geometrid Moths (p. 587), where a list of twenty live species of Geometrids, which 

 grow larger on the Pacific than the Atlantic Coast, is given. The three last stages are described 

 by Mr. Dyar, and show that the larva is closely similar in each stage to the Eastern concinna. 

 Mr. Edwards's descrii)tion of the mature larva agrees exactly with our Rhode Island examples. 



Eyg. — Diameter about U mm. Low hemispherical, the height being about half the diameter. 

 The shell is thin, smooth, and under a triplet not seen to be pitted, but under a half-inch objective 

 the surtace is seen to be divided into regular, moderately large, flat polygonal areas, with slightly 

 raised but distinct edges. No micropyle visible, and no specialized arrangement of the polygons 

 on the apex of the egg. 



Freshly hutched hu-va. — Length, .3 mm. Head large, globular, smooth, and unarmed, a third 

 wider than the body, deep dark, honey-yellow. The body is greenish yellow above, cherry- 

 reddish on the sides; the prothoracic dorsal tubercles are larger and higher than those on the 

 second aiid tliird thoracic segments and connected by a chitinous band, becoming more distinct in 

 Stages 11 and HI. The first and eighth abdominal segments are reddish, including the pair of 

 dorsal tubercles, which are of the same size. The end of the body is held up, uuich as in the 

 fully grown larva, and I mistook it for a Schizura larva, like the ordinary species, until after it 

 had molted, as the tubercles are conical in this stage as in freshly hatched Schizura' of other 

 species. In some individuals the greenish dorsal tubercles are dark at the tip. The glandular 

 hairs are bulbous at the tips, and a few at each end are nearly one-half as long as the body. 



Three days after, June 27, they became 5 mm. in length, the head now small, and the larvi© 

 were preparing to molt, and July 29-30 three cast their skins. 



St(if/e IF. — Length, 4-."i mm. at first. Now the body is like dark opaque varnish in color. 

 The head is dark reddish varnish or pitchy in hue, and dc(udedly narrows above, bearing two 

 blunt knobs on the vertex; it is now wider than the body. The prothoracic shield is larger than 



