210 Mr. F. W. Edwards on 



of the segment. Front tibias practically twice as long as 

 the first tarsal segment. Front tarsi of ^ not bearded. 

 Fourth and fiftii tarsal segments about equal in length. 

 Pulvilli distinct but short, about one-third as long as the 

 claws. Wings somewhat milky-white, not perceptibly 

 punctuate under a magnification of 80. Costa not exceeding 

 the tip of /?4 in $ ^ scarcely so in ? . Cross-vein rather 

 short, thick, somewhat darkened, and nearly vertical. Base 

 of cubital fork distant from base of media by rather more 

 than the length of the cross-vein. Halteres Avith dark stem 

 and yellow knob. Wing-length 2-2*8 mm. ; body-length, 

 cJ 2'7-3"5 mm., $ TS-S mm. 



This may possibly be Zetterstedt's C. ephippium, which 

 was described from Lapland ; the description, however, 

 disagrees in some points, such as the breadth of the pale 

 tibial rings and the separate thoracic stripes of the ? . An 

 extremely similar species, which was determined by Verrall 

 as C. ephippium, is very common in Britain ; it differs from 

 the Spitsbergen form in the absence of pulvilli and slightly 

 in the structure of the hypopygium. 



Mr. Elton notes that eggs laid by this fly on 1. viii. 1921 

 were frozen solid, and still developed into larvae on 

 unfreezing. 



Cricotopus basalts (Staeg.). 



Synonyms: Chironomur^ basalis, Stagor ; C. pavidus, Ilohngren ; 

 ? Trichocladins ursus, Kieffer. 



Spitsbergen : Bruce City, head of Klaas Billeu Bay, 

 22. vii.-14. viii. 1921 ; on shingly raised beach, on hut- 

 window, and ovipositing in pond 1 ; 2 (J , 4 ? . Cape Bohe- 

 man, N. side of Ice Fjord; 0-60 ft., flying over strip of 

 marsh land ; 1 $ . 



Differs from C. glacialis in the entirely l)lack thorax of 

 both sexes, the less distinctly ringed tibiae of the ? , the 

 complete absence of pulvilli, and the structure of the hypo- 

 pygium (see fig. 9). The white lamella) of ihe female 

 ovipositor, the whitish male claspers (though the side-pieces 

 are dark), and the traces of white wings on the tibia?, in my 

 opinion, locate the species in Cricotopus rather than in 

 Trichocladius. Originally described from Greenland, it has 

 since been found in Jan Alayen {Bristowe) . 



Metriocnemus ursinus (Holmgren). 



Bear Island : Walrus Bay, S.E. of island, 22. vi, 1921 ; 

 c. 20 ft., on stones, and under stones in limestone gully, 



