HlSTERHXE 255 



floridcB Mars., also belongs to this subgenus, but it is less elongate 

 than tenebrosus, paler in color, and the transversely arcuate crenate 

 line of the pronotum is shorter, ending within the median line of 

 each elytron, while in tenebrosus it extends fully to that point, with 

 the crenules prolonged anteriorly, being notably different in this 

 respect; it is however perfectly congeneric in the absence of scutel- 

 lurn, long basal joint of the hind tarsi and in the margined front. 



Gnathoncus Duval 



The species of this genus are widely scattered over the entire 

 northern hemisphere, and two species, which however may not be 

 truly generic, occur in the Australian region. Dr. Horn considered 

 them a section of his very composite Group II of Saprinus, and pro- 

 posed some very erroneous synonymy among our described forms, 

 calling them all rotundatus Kug. A specimen of the European 

 rotundatus, carefully determined by Mr. Fauvel, shows that it is a 

 somewhat larger and more remotely punctate species than any of 

 ours, but differing more particularly in the more elongate and 

 gradually tapering outline of the pygidium. I have not seen 

 communis Mars., from Albany, New York, which is more closely 

 punctate throughout than any here described and considered a 

 fully valid species in the Bickhardt list, or interceptus Lee., from 

 San Diego, California, which is said by the author to have the very 

 short basal sutural stria united with the inner dorsal, which if 

 true however, would cause interceptus to be an exception in the 

 genus, one of the most persistent characters of which is a very 

 small arcuation at base, midway between the anterior ends of the 

 sutural and inner dorsal striae, the sutural having a minute hook at 

 base, similar to this isolated intermediate arc. Deletus Lee., is not 

 a synonym of rotundatus, as stated by Horn and Bickhardt, but is 

 valid as a species and occurs only in the northern Atlantic region of 

 North America; it is represented in my collection from Maine 

 (Wales- Frost), New York (Peekskill Sherman), Illinois, Iowa 

 (Keokuk) and Wisconsin (Beaver Dam Snyder). The following 







are three additional species: 



Gnathoncus idiopygus n. sp. Oblong-oval, rather convex, piceous- 

 black, the pygidium dull rufous, the legs red; head minutely, loosely 

 punctulate; prothorax about twice as wide as long, the sides slightly 



