(hi Dijiteru Nemalocera from Sjjilshcrgen. lOli 



XXI. — Jiesults of the Oxford I'luversity Expedition to 

 iSpitsberyen, 1921. — No. 14. Dijdera Nematocera. By 

 F. W. Edwards. 



(I'ublisheil by permifsioii of the Trustees of the British Museum.) 



The Oxford University Expedition to Spitsbergen in 1921 

 bron<rht back a very considerable collection of Neniatocerous 

 Diptera, almost entirely collected by Mr. C. S. Elton. At 

 tbc recpiest of Prof. E. 15. Poulton tlie antbor nndertook 

 tiie examination of tbis most interesting collection, tbe major 

 part of wbicb is deposited in tbe collections of tbe Hope 

 Department of the Oxford University Museum ; except in 

 tbo case of uniques, a representative set of eacb species has 

 been presented by tbe Department to tbe Britisb Mnseum. 



Tbe collection comprised over 700 specimens, representing 

 29 determinable species ; the species were, however, very 

 unequally represented, more than two-thirds of the whole 

 collection appertaining to three species only {Psectro- 

 cladius limbatelhts, Ps. borealis, and Cricotopus glacialis), 

 while of several of the remainder only single specimens 

 were present. As was to be expected, the majority of the 

 species belong to the Chironomidai, but a rather surprising 

 feature was tlie complete absence of Tipulidie (e.vclndiug 

 Trichocera, which is now referred to the Anisopodidre). 

 Several species of Tipulidse are abundant in arctic America, 

 Tipula besselsi being recorded so far north as 82^ ; some 

 might certainly have been expected in Spitzbergen. 



Tbe British ^luseum possesses a fairly extensive collection 

 of Nematocerous Diptera from Iceland (25 species), and I 

 made a comparison between this and the Spitsbergen and 

 Bear Island collection. Much to my surprise, 1 found 

 that there was only a single species {Cricoto/jus basalis) 

 common to both. 1 also compared the 40 species of* Spits- 

 bergen CliironomidjB with tlie British Museum collection 

 of about 400 species of British Chironomidie. The only 

 species which appeared to be certainly identical in the two 

 collections were Chironomus ri]>arius (Mg.), Goet., and 

 Psectrocludius limbatellus (Holmgr.). To these should, per- 

 haps, be added Sciara prcecox, Mg., and Trichocera hiema/is 

 (Deg.j ; the identity of these two, however, is not yet fully 

 established. 



Tbe following are the only important papers dealing with 

 the Nematocerous Diptera of Spitsbergen : — 



18G9. IIoLMOUKN, A. E. " Bidrag till Kiinnedomen oin Heeren Eilands 

 och Spetsbergons Insekt-tauua." K. Sveiisk. Vet.-Ak. lluudl. 



Ann. tfc Mu</. N. Hi si. Scr. 9. V<d. x. 13 



