14 



are very slender, almost filiform, and there is a cluster of black 

 scales in the fringe near the middle of the hind margin of the 

 third feather. 



This genus was established by Lord Walsingham on a single 

 species, pygmceus, of which his lordship took three specimens near 

 Milville, in Shasta County, California, on the llth of July, 1871, 

 one of which with his characteristic generosity he gave me. As 

 this single co-type is all I have, I do not feel like injuring it to 

 study the venation or genitalia. Mr. Meyrick, in his "Hand- 

 book of British Lepidoptera," has given the venation of the fore 

 wings probably of T. paludum Z. as follows : 2 out of 4 or absent, 

 3 absent, 7 and 9 absent, 10 from near 8 or absent, 11 from near 8. 



Hofmann gives a description of the male genitalia and a figure 

 of a paramere of T. paludum. He states that the genitalia of the 

 male are distinguished by the remarkable form of the claspers, 

 which are long and narrow, hollow within, and with a broad, bell- 

 shaped, bristly appendage. The tenth dorsal plate is obtusely 

 triangular, arched and bent down at the end. The ninth dorsal 

 and ventral plates offer nothing especially worthy of remark. 



SYNOPSIS OF THE SPECIES. 



Expanse of wings, 10 mm. or less, . . pygmceus. 



Expanse of wings, 17 mm., .... ochrodactylus. 



Expanse of wings, 20 mm., . . . . lobidactylus. 



TRICHOPTILUS PYGMJEUS. 



Trichoptilus pygmceus Wlsm., Pter. Cal. and Ore., p. 64, 

 Plate III., fig. 15 (1880). 



Expanse of wings, 10 mm. Head and thorax pale fawn color; 

 antennae slightly pubescent, marked above with fawn brown and 

 white alternately; palpi whitish touched with fawn color. Ab- 

 domen whitish, with a tinge of fawn color on the sides and above 

 posteriorly. Legs white, dotted and barred above with fawn 

 brown ; spurs white, and at their origin the legs are thickened 

 with fawn brown scales, among which project some which are 

 white and almost erect. Fore wings very pale fawn color, dusted 

 with fuscous brown scales along the costa, especially above the 

 base of the fissure and near the base of the hind margin. Two 

 indistinct white stripes cross the lobes of the fore wings, one 

 beyond and the other before the middle^ cutting the fawn-colored 

 fringes on each side. Hind wings pale grayish brown, with 



