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NOTES OX CULICIDAE, WITH DESCRIPTIONS OF NEW SPECIES. 

 By F. W. Edwards, B.A., F.E.S. 



{Published hy permission of the Trustees of the British Museum.) 



Genus Anopheles, Mg. 

 A. (Coelodiazesis) plumbeus, Hal. 



The life-history of this species has recently been fully described by Christophers 

 (Ind. Jl. Med. Res., iii, Jan. 1916, p. 489) from larvae obtained in tree-holes in the 

 neighbourhood of Simla. It is somewhat surprising that a species of Anopheles should 

 have such a wide range, especially since tree-breeding mosquitos are usually more local 

 in their distribution than other kinds. I believe, however, that Christophers was 

 perfectly correct in his conclusion that A . barianensis, James, is the same species as 

 A. pliiuibeus, Hal. 



I had on several occasions looked in vain for larvae of A. plumbeus in tree-holes and 

 elsewhere, until in April last I succeeded in finding numbers of larvae, associated -snth 

 those of Ochlerotatus gen iculatus (see below) in holes in beech trees at Burnham Beeches, 

 Bucks. These larvae agree closely with Christophers' description and figures, the only 

 difference I can detect being that the " triradiate spines " to which Christophers refers 

 do not seem to be so strongly developed. 



The larvae were kept for a fortnight in the water in which they were found, together 

 with some of the leafy debris which it contained, but they appeared to make no growth 

 at all. The same was true of specimens which were isolated in tubes without debris, 

 but ^^'ith small larvae of 0. geniculatus. After this lapse of time fragments of crushed 

 flies were added to the tubes and also to the main receptacle. All the Anopheles larvae 

 at once clustered round and fed voraciously, some of them pupating very shortly 

 afterwards. These experiments entirely confirm Christophers" conclusion that the 

 larvae depend mainly for their food upon insects which fall into the water of the tree- 

 holes ; they do not appear to feed, as does 0. geniculatus, on the vegetable debris at 

 the bottom ; nor, it seems, do they attack these other larvae, although the latter 

 were always present in the tree-holes in which I found A. plumbeus. 



According to Dyar and Knab, the larvae of the North American A. (Coelodiazesis) 

 barberi prey upon those of Aedes {Ochlerotatus) triseriatus (which is the North American 

 representative of 0. geniculatus). From this diflference of habit, as well as from the 

 quite considerable larval differences shown by the figure in Howard, Dyar and Knab's 

 monograph, it seems probable that A. barberi is a distinct species from A. plumbeus. 

 I have not however seen the American form. A. plumbeus is a common blood-sucker 

 in wooded districts in this country, often biting in the daytime. 



There evidently may be at least two broods of A. plumbeus in the year, as I found 

 young larvae in a hole at the base of a beech tree in Cassiobury Park, Watford, on 

 21st August. In this case also the Anopheles larvae were associated with those of 

 0. geniculatus. 

 (C326) Wt.P12/109. 1,0«0. 1.17. B.& F.Ltd. G.11/1. * 



