AMERICAN COLEOPTERA. 251 



HYDROCHARIiii, Latr. 

 Prosternum acutely prolonged behind. 



Sixth joint of antennae much larger than the seventh; maxillary palpi as 

 long as the head and thorax castiis. 



Prosternum not prolonged, obtuse at tip. 



Sixth joint of antennae smaller than the seventh. 



Maxillary palpi as long as the head. Color of body piceous with faint 



tinge of bronze obtusatui^. 



Maxillary palpi short. Surface of body with glaucous coating. ..glaiicus. 

 Tn casfus the crest of the prosternum forms nearly a continuous line 

 with that of the meso-metasternum, while in the other two species the 

 two form a very oblique angle. 



B. gI(rKC7(s, Lec. — This species was first described as H. Ihipatus 

 Lee, Proc. Acad., 1855, p. 309, from a very badly discolored speci- 

 men of (jlaucus, the latter having been described six yeaK later, Proc. 

 Acad., 18G1, p. 341. By an error of the pen the nammdineatus ap- 

 pears as II. subsfriafus, List Col. N. A., 1863, p. 18. I adopt the 

 later name fflaucus, because it is more appropriate and belongs to the 

 true species and not to a discolored variety, and also on account of the 

 confusion of the other name. No injustice is done to the orio-inal 

 describer and there is no intermediate synonymy. 



H. grmulis, Zimm., Trans. Am. Ent. Soc-, 1869, p. 250, is merely a 

 female of ohtusatus. (g. h. h.) 



BEROiSUS, Leach. 



B. styllfirus., Horn, should be removed from its present position in 

 the list and placed near infuscatus. The last ventral segment is simi- 

 larly toothed in the two species, my original description having been 

 made from a specimen accidentally deformed. The mesosternal spine 

 will at once distinguish it from any other species. (g. h. h.) 



Sepiduhmi cosfatum, Lec, Trans. Am. Ent. Soc, 1874, p. 47, 

 should be referred to epimetopus, Muls. (g. h. h.) 



TROPISTERKUS, Sol. 

 Prosternal groove open anteriorly. 



Thorax and elytra with pale margin, the latter with discal yellow vittEo. 



striolatns. 



Prosternal groove closed anteriorly. 



Thorax and elytra margined with yellow 1. 



Thorax and elytra unicolorous 2. 



1. — Elytra! limb suddenly broader at basal third lilllbalis. 



Elytral limb narrow, equal lateralis. 



2. — Last ventral segment without spinous crest 3. 



Last ventral segment with spinous crest 4. 



