Insects, 4921 



mologists from the streams and ponds at Hebden Bridge, York 

 shire. 



9. JL nigrolineatus, Schon. This appears to be the H. 9-lineatus of 

 Rudd, and is well figured by Schonherr : it was unknown as a British 

 species until I took a single specimen in Loch Fad, in the Isle of 

 Bute, the end of July, 1825, and both sexes in the same lake the 9th 

 of August, 1834; subsequently Mr. Dale and myself found it not un- 

 common in Woolmer Pond, four miles to the east of Selborne, 

 Hants. 



10. H. latus, Curt. Brit. Ent. fol. 343. Of this distinct species 

 Mr. Dale first took a pair in his pond at Glanville's Wootton : I 

 named it H. latus in the first edition of my ( Guide/ published in 

 1829, and described it in i British Entomology.' Mr. Rudd subse- 

 quently compared specimens he had taken with the one in my 

 cabinet, and of course adopted my name, and gave it to the author of 

 the 'Manual:' it is consequently my H. latus, not Mr. Rudd's, 

 although it is so given by Stephens and others. Some time after I 

 described it, Sturm gave a very good figure of it, under the name of 

 H. ovatus. 



11. H. cambriensis, Curt. Brit. Ent. fol. 343. I know not what 

 became of the specimen I described, taken in Wales ; it might be a 

 variety of D. palustris, Linn., which is the opinion of Mr. Murray ; 

 but I apprehend the specimens ticketed in Stephens' cabinet as 

 H. cambriensis cannot be admitted to identify the unique specimen 

 taken by Mr. Davis. 



12. H. planus, Fab. The little species thus named by Marsh am is 

 quite different to the Fabrician insect, and may prove to be the 

 H. umbrosus of Gylleuhal ; but the specimens named H. planus in 

 Stephens' cabinet are undoubtedly H. melanocephalus. On the 28th 

 of April, 1842, I took a single specimen of an Hydroporus, closely 

 allied to, if not the true H. planus: I found it under a stone in a 

 pond used for sheep-washing on the downs near Wilton. This 

 specimen, which I was enabled to compare with examples of the 

 Fabrician species sent to me by the late Dr. Sturm, I conceived was 

 identical with the true species; but Dr. Power having recently 

 examined them, he is disposed to think that the Wilton and Fabri- 

 cian H. planus are distinct: if such prove to be the case I wish to 

 name my specimen H. Harrisii, in compliment to an esteemed friend 

 who took a great interest in the 'British Entomology' during its 

 progress through the press. 



xiit. 3 E 



