192 Trans. Acad. Set. of St. Louis. 



Gnypeta Thorns. 



The European fauna appears to include but three members 

 of this genus, thus contrasting greatly with the American 

 which is very rich, not only in species of Gnypeta but in sev- 

 eral allied genera as well. In some more elongate and slender 

 forms it seems to make a rather close approach to Tachyusa, 

 to which genus a number of its species were originally as- 

 signed, but the resemblance is more apparent than real. The 

 very narrow claviform abdomen and strongly angulate exter- 

 nal tips of the elytra will readily distinguish the true Tach- 

 yusa from any Gnypeta, without referring at all to the very 

 approximate coxae and acute mesosternal process, which, in 

 Gnypeta, is always broader. In Gnypeta the apices of the 

 elytra are never more than feebly oblique or moderately angu- 

 late at the sides externally, and, even when the basal impres- 

 sions of the abdomen are strong, they are never medially 

 carinate as they are in Tachyusa. The antennae are almost 

 as diversified in length and thickness as in the genus Aleo- 

 chara, enabling us to suggest a very convenient primary divis- 

 ion among the numerous species. The general sculpture is 

 fine but much less so as a rule than in the allied genus JEuUusa, 

 of the Sonoran fauna, and is usually much denser, frequently 

 giving the integuments a duller appearance and the color is 

 almost universally deep black, contrasting with the equally 

 prevailing pale coloration of that genus. The twenty-two 

 species represented in my cabinet can probably be identified 

 through the following outline descriptions : — 



Antennae short, although generally somewhat longer than the head and 

 prothorax together 2 



Antennae longer, always very much longer than the head and prothorax; 

 apex of the elytra moderately angulate posteriorly at the sides 8 



2 — Antennae evidently longer than than the head and prothorax, the sub- 

 apical joints never more than slightly wider than long; basal impres- 

 sions of the abdomen more or less sparsely punctured or subimpunctate ; 

 species of the carbonaria type 3 



Antennae not longer than the head and prothorax, more compact and In- 

 crassate distally, the subapical joints strongly transverse; basal im- 

 pressions of the abdomen coarsely and densely punctured 7 



