4 Bergroth, On some Limnobiinae from Northern Europe. 



from analogies in several other apterous insects, the posi- 

 tion of the eyes at the anterior end of the head seems to 

 be a such specialized character connected in some way with 

 the lack of wings, and the strong development of the hairs 

 is doubtless also an acquired character. The incrassation 

 of the male hind femora is apparently due to the singular 

 manner in which the copulation takes place, as witnessed 

 by Gravenhorst and Mik. When the life history and 

 habits of Chionea are better known, it will be easier to see, 

 which of its external characters are adapted to its habits 

 and which are primary, and then its true affinities will be 

 more evident. The antennae of Chionea are called abnor- 

 mal" by Osten Sacken, and they are no less so in 

 Crypteria. I do not share Osten Sacken's opinion that 

 merely the incrassation of the male forceps and the stout- 

 ness and hairiness of the legs are sufficient grounds to 

 consider Chionea closely allied to Psiloconopa. 



In the descriptions given below I have used the Com - 

 stock-Needham nomenclature of the venation with a 

 few exceptions in which I mostly follow Enderlein. To 

 prevent confusions with cell R t the cell R is called Rs (ra- 

 dio-sectorial cell). The cells which in the Comstock- 

 Needham nomenclature bear the awkward names „first 

 second median cell" and „second second median cell" (1 st 

 M 2 and 2d M 2 ) are here called respectively discal cell and 

 second median cell. As the „second anal" vein is an inde- 

 pendent vein, not a branch of the (first) anal vein, it is called 

 the axillary vein. 



The figures are drawn by me except the three figures 

 of the propygium of Crypteria which I owe to the expert 

 hand of Prof. C. Lundstrom whose skill in softening and 

 preparing dry propygia is well known. 



Crypteria nov. gen. 



Antennae duodecim-articulatae, articulo primo oblongo, 

 secundo globoso adjacentibus multo latiore, tertio elongate 

 conico, ceteris oblongis, gracillimis, ultimo obtriangulari, 



