HISTERIDiE. . 121 



DESCRIPTION. • 



Body subelliptical, minutely punctured ; underneath black somewhat hairy with very short incon- 

 spicuous hairs, above lurid or dirty-yellow, glossy, more conspicuously punctured. Head black with 

 a quadrangular yellow spot before each eye; nose gibbous, separated from the front by a transverse 

 angular line ; palpi and antenna; dirty-yellow, the latter with a black knob : prothorax with a dark, 

 discoidal, subquadrangular spot, which does not reach the anterior margin : elytra with a furrow 

 adjoining the suture ; shoulders with a dusky line : tibia; and tarsi dusky rufous. 



Variety B. Larger, dusky rufous above, spots before the eyes larger and subtriangular : black 

 spot on the prothorax wider but not so near the anterior margin ; shoulders of 

 the elytra without a dusky line. 



The American specimens have no black spots contiguous to the discoidal one on the prothorax, 

 noticed by Major Gyllenhal and Mr. Stephens. Variety B. is very like Variety y. of Stephens 

 (Var. c. Gyllenh.) Hydrophilus dermestoides of Forster and Marsham, but the front is spotted. 



Most modern Entomologists seem agreed in placing the Sphceridiadce next to 

 the Philhydrida, and the genera that connect them are clearly Hydrobius and Cer- 

 cyon. The insects of this last genus indeed are generally terrestrial, hut one species 

 is strictly aquatic — I allude to Cercyon aquatlcum, 5 which Fabricius has described 

 under the name of Hydrophilus hamorrkoidalis, 6 and which was sent me as such by 

 Gyllenhal so long ago as 1802. Afterwards in his Insecta Suecica, he denominates it 

 Sphcerldium hamorrhoum. 7 This family, as well as the Byrrhidce, has considerable 

 affinity with the Histeridcs, to which it approaches by Abrceus ; so that the aquatic 

 branch which leads from the predaceous beetles here again seems to meet the 

 terrestrial, and which by means of the Histeridce proceed, as it were, together to 

 the Lamellicorn tribes : Hister of Linneus, therefore, seems rather an osculant 

 group, than a part and portion of the great section last mentioned. 



5 Step. Illustr. Mandib. ii, 138, 6. 6 Ent. Si/st. i, 185, 16. 



7 i, 107, 9. Mr. Stephens' Cercyon heemorrhoum ( Illustr. Mandib. ii, 143, 23) must therefore be a different species. Mr 

 Stephens, both in his Catalogue (64, 658, 32) and in the work just quoted (1 45, 32,) has referred to my MS. Catalogue, 

 for a name he has adopted ; but the name is incorrectly written. Instead of Sphceridium convexium, in my Catalogue it 

 stands, as it should, as the neuter of convexior, S. convexius. 



R 



