294 Capt. F. Balfour-Browne on 



since seen — a few in the Dublin Museum collection, a few in 

 the Natural History Museum collection, some in the collection 

 of Dr. G. W. Niciiolson — belong to this species. 



The discovery o£ the existence of this northern species in 

 the British fauna I attribute to Dr. Sharp, although he tells 

 me he remembers nothing about it and cannot now find in 

 his collection the specimens which I thought I had seen there ; 

 but it was Capt. Ste. Claire Deville, of Epinal, France, who, 

 in 1911, suggested to me the possibility of its existence in 

 these islands. I had sent him a number of British water- 

 beetles, and among them one or two English specimens of 

 what I had named "2). dtpressus,''^ and in acknowledging 

 the receipt of them he said : " I agree with you for the names 

 of all Dytiscidge but Deronectes depressus, which seems to me 

 to be our D. elegans, Sturm. The true depressus, an Arctic 

 species, which I have from Russia, Norway, and also from 

 Easte n Pyrenees, is perhaps also British " *. 



Later in the year I was in Brockenhurst, and I mentioned 

 this matter to Dr. Sharp, who, as I think, agreed that our 

 common form was " elegans" and showed me two ratiier 

 large and dark specimens of Deronectes from some eastern 

 Scottish locality — I think it was L. Brandy in Forfarsliire — 

 which he considered to be the ''^depressus" of Fabricius. 



After casually looking through my specimens, and failing 

 to recognize any differences among tliem, I let the matter 

 drop until in July 1915 I came across a statement by Tiiomas 

 Bold, who, speaking of Hydroporus elegans, Illiger, sail : — 

 " I take a strongly marked var. of tiiis common insect in 

 Talkin Tarn, Cumberland. At first sight they much resemble 

 B. 12-pudulatus, being much larger and darker coloured 

 than the specimens of elegans from running water. Some 

 have the eljtra wholly black, except a narrow yellow margin, 

 others are more or less lineated with yellow, and scarcely any 

 of them have the spotted appearance characteristic of the 

 species "f. This re-aroused my interest in the subject, and, 

 as I was just starting to motor to Scotland, I determined to 

 make a slight detour so as to visit Talkin Tarn on my 

 way. This small tarn lies about 9 miles east of Carlisle, at 



* Postcard, May 23, 1911, 



t '* Capture of some of the rarer Hydropori in the North of England," 

 Zoologist, xii. pp. 4193-4195 (1854). Vide also ihid. xi. 1853, pp. 3924, 

 3925. Report of Proceedings of Tyneside Nat. Field Club Meeting, 

 Mar. 30, 1853, where a large dark var. of H. elegans ? from TalMn Tarn 

 is mentioned. 



