ON THE H EMEROB1 I N AE OF JAPAN. 



13 



Family HEMEROBIID/E. 

 Subfamily HEMEROBIINAE. 



The subfamily Hemerobiina; can scarcely be sharply distinguished 

 from the Osmylînae. The condition of subcosta, which Banks has utilized 

 as distinctive criterion between the two subfamilies, is not always adequate 

 enough for the purpose, since in certain Hemerobian genera, e. g., Ninguta 

 and Sympherol ius, some species have the said vein united to radius near 

 apex of forewing in a manner somewhat as in some Osmyline forms. 

 Nevertheless, for the sake of convenience I follow Banks (1. c.) in denning 

 the subfamily as follows : 



Ocelli absent; antennes moniliform, not pectinate in either sex. 

 Prothorax short, being broader than long. Wings zuith few erossveins, 

 commonly arranged in tzco gradate series ; usually several sectors present, 

 zvh.cn but one, it is connected to radius by not more than four crossreins ; 

 sul costa almost always not united zuith radius near tip of zunigs. Legs 

 slender ; hind tibia commonly dilated in middle. Ovipositor of the female, 

 when exserted, very short. 



The two tribes into which I divide the subfamily, are characterized as 

 follows : 



Tribe Neurorthini. — Female zuith ovipositor, which is short, stout and 

 split on the ventral side (as in Sisyra). Branches of radial sector on for e- 

 iv ing arise from common stalk, thus shozuing only one radial sectcr. (See 

 PL I, fig. 1). 



Tribe Hemerobiini.'-' — Female zuithout exserted ovipositor. Branches 

 of radial sector on forewing arise separately from radius, thus shozuing 

 moie than tzuo radial sectors. (See Pl. I, fig. 2-6). 



The presence of exserted ovipositor in the female of Xcurorthtis, 

 similar to that of the Osmyline genus Sisyra, distinguishes that genus from 



1) Trans. Amer. Ent. Soc, xxxii, p. 23 (1905), and xxxix, p. 211 (igij). 



2) The old name " Hemerobiini " of Latreille is here retained with extensive alteration in sense. 



