Insects. 505 1 



limits of this paper will allow : they are represented by Erichson 

 (Kaf. d. Mark. Branden), by his H. aquaticus, H. granulans, and H. 

 griseus; by Mulsant, by one species only, H. granulans, which single 

 species consists of var. A. arcuatus, var. B. obscurus, var. C. granula- 

 ns, var. D. minutus. 



So far as a careful collation of different and well- stored cabinets of 

 British specimens, with the descriptions of these authorities, will 

 decide the question, it would appear that in England at least there 

 are two, and but two, species ; that is, an insect larger, darker, though 

 most variable in size and colour, — the H. aquaticus, Linn. (= pro- 

 bably H. granulans, Linn.); and a species smaller, narrower, elytra 

 always pale testaceous, and anterior and lateral margins of thorax 

 usually pale, — H. griseus, Herbst. 



In stating this as the result of long and minute investigation, I 

 would notice the impossibility of coming to a satisfactory conclusion 

 on the point in the absence of large series of specimens from each of 

 as many different localities as possible. Dr. Power's cabinet con- 

 tained perhaps 150 examples of these two species, and mine about 

 300. In a smaller series the probable absence of specimens connect- 

 ing sets of varieties would tempt to break the group up into more spe- 

 cies ; and there would not be the same satisfactory evidence that, 

 notwithstanding these connecting individuals, two distinct species 

 could be established as indigenous. 



6. H. dorsalis, Marsh. Rare. Hertford ; Norfolk ; also at 

 Wandsworth Common, by Dr. Power. The specimens which I have 

 examined agree as little with Stephens' description as with his figure 

 (Illus. ii. pi. xiv. 1). The insect appears to be tolerably constant in 

 colour; elytra dusky black, with two testaceous well-defined patches 

 at apex, and also an irregular band of the same colour across the 

 shoulders. 



7. H. pumilio, Erichs. A distinct and beautiful species. I know 

 of only two British examples, one in each of the cabinets of Dr. 

 Power and Mr. Waterhouse, taken, at the same time, by Mr. Bates, 

 of Leicester, among the debris of a flood ; in general appearance not 

 unlike some small specimens of H. aquaticus, Linn., but totally dis- 

 tinct by well-defined markings on elytra. The H. pumilio of 

 Stephens, Cab. and Man., is H. nanus. 



8. H. nanus, Sturm. Rare. Sufficiently described by Stephens. 

 Sturm's figure is bad. Most of the specimens I have seen were 

 taken, twenty years ago, in the Cambridge district ; Dr. Power took 

 it not unfrequenlly ; and in the cabinet of Mr. Babington, St. John's 



