AMERICAN LEPIDOPTERA. 175 



surface. Some white scales linearily arranged within the extra anal 

 aiiti'le on the margin. 



Head and body, above, bhackish, with longer and spnrsely scattered 

 pale hairs. Antennae, black, prominently annulated with white; club, 

 black, tipped with fulvous. Palpi, black, with some longer whitish 

 hairs beneath, f^yes, very narrowly margined with white behind. Un- 

 der thoracic surfiiee and legs at base, clothed with long whitish hair. 

 Tarsi, testaceous, with lateral white scales; tibiae marked within with 

 whitish. Abdomen, beneath, obscure whitish. 



Expanse, 1.10 inch. Length ofhody, 0.40 inch. 



Habitat. — Atlantic District. (Maine! to Pennsylvania!) 



This species is intermediate between Thecla augustus, Kirhi/, (T. 

 ougiisfinitii, Westw.) and Thecla irus, as illustrated by Boisduval and 

 LeConte, and is apparently associated geographically with the former. 

 It differs from T. augustus, in the ornamentation of the wings beneath 

 and the brighter colored antennal tips. It is smaller than T. irus and, 

 while resembling it in the ornamentation of the wings beneath, is at 

 once distinguished by the absence of the inner purplish basal space 

 circumscribed by the arcuate white line. From Thecla arsace, Bdo. 

 and Ler., it differs by the markings of both wings beneath; the shape 

 of the transverse lines is very different, and these are not followed by 

 white scales in LeConte's figures, while Thecla henrici has not the 

 brown discal patch and the series of interspaceal, subterminal, brown 

 blotches on the secondaries beneath. 



To the kindness of Mr. Scudder we owe a specimen of this species, 

 ticketed as from "Maine" (Smith), which does not differ from a num- 

 ber of specimens from the vicinity of Philadelphia, except in that the 

 secondaries show a very few white scales, very narrowly arranged, edg- 

 *ing the secondaries linearily along external margin. There is a vari- 

 ation in the extent of the brown apical space on the secondaries be- 

 neath. In some specimens this is encroached on by the hoary shading 

 so that it is nearly lost. On the under surface of the primaries the 

 veins margining the cell are most prominently discolored with blackish. 

 In the males the brighter shadings of the primaries above are obsolete. 

 With reference to Thecla augustiuus, Westw., (^Tliecla awjiiatna.W Kir- 

 by), it may be remarked, that Fabricius' Hesperia augustus, Ent. Syst., 

 3, p. 275, will very probably be irrecoguizable. The description : — 

 ''H. R.-alis caudatis albis; limbo fu.sco, subtus ferrugineo flavoque 

 variis, posticis strigis duabus cinereis " — refers to a tailed species, and 

 a reference is made to " Papilio Augustus, Jon. fig. pict. (5, tab. 3, 



