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MR FRANK BALFOUR-BROWNE ON 



species, which he named H. picicrus, a form which is less elongate and more rotund 

 than the typical H. fuscipes and has thicker and more pitchy tibise. The pubescence 

 of the hind femora also is not quite so extensive, and the punctuation of which it is the 

 accompaniment is not quite so dense and fine (Sharp, D., Ent, Mo. Mag., xxi., 

 84, 5, 1884-85). The elytral striae are more strongly punctured and therefore appear 

 to be rather deeper than in H. fvscipes, and the punctuation of the upper surface is, as 

 a rule, more coarse. The penis is also certainly broader than in the typical form. 

 Although some Coleopterists have followed Thomson in regarding H. picicrus as 

 specifically distinct, others, and probably the majority, have regarded it merely as a 

 variety of H. fuscipes. 



After carefully comparing a number of specimens of H. fuscipes and picicrus, I am 

 inclined to think the latter is not entitled to specific rank, chiefly because there are all 

 grades of intermediate forms between the two extremes. H. picicrus seems to prefer 

 a different environment from H. fuscipes, although there are perhaps few places where 

 either form exists to the complete exclusion of the other. H. picicrus is more common 

 on peat mosses than is H. fuscipes, while it is certainly much scarcer on salt-marsh 

 areas than is the latter. I think also H. fuscipes is less common in the north and 

 picicrus less common in the south, but of this T am not altogether certain, and even if 

 it is so, the distribution may be owing to the distribution of peat mosses. 



Characters of the Imago. 



Without entering into a detailed description of the imago, I wish to refer to certain 

 characters which are of special interest. The head bears the two antennae which are 

 of the type found in all the Hydrophilidae (fig. 34). They consist of nine segments, 

 the basal one long and slightly curved, the next four short and simple. The sixth from 

 the base is somewhat saucer-shaped, the concave surface being outwards and the attach- 

 ment being central. Above the saucer-shaped segment are two more or less gobular 

 segments each flattened above, and upon them is the apical gobular segment. The 

 three terminal segments are dark brown in colour and are thickly covered with short 

 stout hairs, while the upper face of the saucer-like segment bears a number of short 

 tubercles from the apex of each of which stands up a long fine hair. The colour of this 

 segment, and of all those below it, is pale testaceous. 



The antennae are attached to the head immediately in front of each eye, and when 

 at rest lie backwards along the ventral margin of each eye and just below the sides of 

 the head. 



The Mouth Parts. 



The labrum is long and narrow, being slightly indented on the free border in the 

 middle. It can be seen moving up and down when the beetle is feeding. The right 

 and left jaws (figs. 1 and 2 ; 32 and 33) differ somewhat from one another. They are 



