Crane-flies 17 c 



European student to critically study the existing types and compare the authen- 

 ticated Palsearctic species with a great series from America and elsewhere, h 

 this is done it may be that the correct synonymy can be determined. It is 

 scarcely possible for an American worker to attempt the problem. at least under 

 present European conditions, chiefly because of the impossibility of >tudying 

 the types of the European species still existant and the added difficulty of obtain- 

 ing authentically named specimens of the European sperirs. the Kuropean 

 specialists, apparently, being as much in doubt concerning the true sialus of 

 the group as are the American workers. 



Until a, very recent date the genus Trichocera, together with the related 

 genus Ischnothrix Bigot, from Cape Horn, was included as a member of the 

 Tipulid tribe, Limnophilini. A critical study of the immature stages by Johann- 

 sen, Keilin, de Meijere, Malloch, and others has shown the utter impossibility 

 of such an assignment and it seems better to give it subfamily rank in the 

 family Rhyphidse. 



Trichocera sp. 



The present collection included three specimens of Trichocera sp., from 

 Bernard harbour, Northwest Territories, June 18, 1915, collected by F. Johansen; 

 two males, Nos. 1301 and 1302 and a female, No. 1300 D. 



IMMATURE STAGES. 



The present collection of Canadian Arctic crane-flies included a surprising 

 amount of life-history material. This was of very great interest since our knowl- 

 edge of the younger stages of any Arctic crane-flies is almost negligible. Unfor- 

 tunately, very little of the material had been reared and consequently the 

 placing of the species has been attended with considerable doubt and difficulty. 

 As a rule it scarcely pays to describe or figure undetermined larvae or pupae 

 unless they show conspicuous points of difference in their structure, have a 

 peculiar habitat, or else, as in the present case, come from a region where prac- 

 tically nothing is known concerning the early stages. These Arctic crane-flies, 

 especially of the Tipuline group, are sometimes as beautifully patterned in the 

 larva as they are dull and obscure in the adult. The biological data that were 

 supplied by the collector are incorporated with each species concerned. 



HEXATQMINI. 



In another paper, not yet published, I have endeavoured to correlate the 

 present classification of crane-flies, based entirely on a study of the adult flies, 

 with a critical survey of all the immature stages that I could obtain. Among 

 other things this study seems to indicate that the tribe Hexatomini is not as 

 clearly set off from the related groups as a study of the adults alone would 

 imply. Several of the groups that have hitherto been considered subordinate 

 groups of the genus Limnophila, such as Ulomorpha, Lasiomastix, Dicranophrag- 

 ma, Poecilostola, etc., all seem now to be more properly referable to the Hexato- 

 mini, or at least closely allied to Eriocera, Penthoptera, etc. The present species 

 has not been reareol and its true affinities must be left in doubt, but I believe 

 that the reference given below will be not entirely erroneous. 



Poecilostola supposition. 



This is a small group of flies including seven or eight species of the Palse- 

 arctic region with representatives occurring in Japan. Although no adults of 

 this group of flies or, indeed, any of its relatives have yet been taken in the 

 Canadian Arctic I feel very little hesitation in referring the present larva to the 

 neighbourhood of this genus. It may belong to the subgenus Phylidorea Bigat 

 of the genus Limnophila Macquart. 



Vol. iii 46963 2 



