— 478 — 



3-rd apical forks triangular and beginning nearly at one level; posterior 

 wings subhyaline, slightly darker at hind margin, 1-st apical fork deri- 

 ving from apex of the discoidal cell. 



?. 9-th sternite with two lateral excavations; subgenital plate 

 small, its side-lobes rather large, broad at base; dorsal plate narrow, 

 broader at base, with the apex slightly thickened. 



Length of the body 13 mm. 



This species ressembles D. unicolor Banks (from Washington 

 Territory). But having seen no specimens of the last named species, 

 and the structure of its genital appendages being entirely unknown, 

 I cannot identify my specimens with D. unicolor. 



Gen. Praecosmoecus, gen. n. 



?. Spurs 1.3.3; last tarsal joint without spines; discoidal cell 

 of the anterior wings very long, 1-st apical sector deriving from the 

 middle of it; 2-nd and 3-rd forks sessil, thyridial cell shorter than the 

 discoidal one. 



$. 9-th ventral segment with two lateral excavations; subgenital 

 plate narrow, side-pieces with minute pedicels. 



The genus belongs to the group of Dicosmoecus McLaclil. 



10. Praecosmoecus kamtshaticuSy sp. n. 



(Fig. 1). 

 1 $ . Kamtshatka. 



Head reddish-yellow; 1-st joint of the female maxillar palpi short, 

 2-nd, 4-th and 5-th nearly equal, the 3-rd slightly longer; labial palpi 

 short; thorax yellowish-testaceous, sides of mesonotum and metano- 



tum brownish; legs yellow; ab- 

 domen reddish above, paler be- 

 neath. Anterior wings uniformly 

 yellowish, clothed with short 

 adpressed yellow hairs, posterior 

 wings slightly paler; radius of 

 the anterior wings (fig. 1) straight, 

 discoidal cell narrow and more 

 than twice longer than its pe- 

 dicel, 2-nd fork triangular; poste- 

 rior wings not very broad, dis- 

 coidal cell regular, nearly as long 

 as its pedicel. 

 ?. 9-th ventral segment with two lateral deepenings; hind mar- 

 gin extending into two finger-shaped yellow processes, directed back- 

 wards; subgenital plate tongue-shaped, narrow, its side-lobes shorter, 



Praecosmoecus kamtshaticus, 

 sp. n. Wing venation. 



Revue Russe d'Entom. XIII. 1913. .№ 3—4. 



