5oo 



WARO NAKAHARA: 



In his recent work on the Osmylidae (I.e.), Krüger has created 

 numerous new genera, many of which are without doubt to be ranged 

 under the Tribe Osmylini as defined above. Whatever be the true 

 status of these genera, they may be considered to be of no concern to 

 the Japanese species known at present of the tribe. The latter I refer 

 to the two old genera, Osmylus and Spilosmylus, which may be 

 distinguished from each other in the following way : 



Cubitus of hindwing with a branch running for most part along 



Cubitus of hindwing with a branch, which, instead of running 

 along with it, makes its course obliquely towards inner margin 



Here a few words about the genital appendage of Osmylus. 

 Needham (I.e.) has described from the alleged male of Parosmyhis 

 prominens, a form later referred to Osmylus, a curious appendage 

 depending from the hindmost abdominal segment and tentatively 

 called by him the " sperm conveyor." He said : " This is boat-shaped 

 in outline, with a pair of minute palps on the bilobed posterior end. 

 It appears to be capable of being swung in and out on a more or 

 less flexible and muscular pedicel, and when swung inwards, its point 

 must be close to the sperm orifice." 



This interesting organ is present in several specimens examined 

 by me, but contrary to Needham 's statements, I have found all those 

 individuals to be females, not males. A living specimen of Osmylus 

 hyalinatus with the organ laid eggs in the paper bag in which it was 

 held in captivity. This shows that both Petersen and Banks are right 

 in considering specimens without the organ to be the males. 



The male genital apparatus of Osmylus is characterized by the 

 presence of a pair of peculiar free sacs. In the male of Spilosmyhts 

 these are wanting, though the female is in possession of the boat- 

 shaped organ before referred to. 



with and parallel to it 



Osmylus. 



of the wing 



Spilosmyhts. 



