NORTH OF MEXICO. 



365 



TRIBOLIUM, Mac Lea,/. 



Tribolium, MaoLeay, Annulos. Javan., p. 47. 



The mentum in this genus is very nearly square, with rounded anterior angles. The 

 last joint of the maxillary palpi elongate oval, truncate at apex. Antennae slender last 

 three joints suddenly dilated, forming a flattened club, truncate at apex. The epipleuree 

 are entire but extremely narrow at tip. Anterior tibia' very feebly dilated and percepti- 

 bly broader than those of the middle pair. 



Two species are known in our fauna. 



T. ferrugineum, F;il>., (Trogosita); Wollaston (Tribolium). 



T. madens, Oliarp., (Tenebrio); Redtenbacher (Tribolium). 



The former species is ferruginous, the latter black. Length .16-.20 inch. The latter 

 species is the larger. As these two species are imported and full descriptions and details 

 of synonymy are given in many readily accessible works on European Coleoptera, it is 

 dee i ned unnecessary to repeat them. 



Both species are found abundantly wherever meal or grain is stored. 



DICEDTJS, Lee 



Dioedus, Class. Col. N. A., 388. New Speoies, p. 182. 



Mentum trapezoidal, narrower behind, anterior angles distinct, convex along the me- 

 dian line and coarsely punctured. Last joint of maxillary palpi elongate oval, scarcely 

 compressed. Antennae with the first joint cylindrical, thick, last two joints suddenly 

 broader, compressed and pilose, the last joint being the larger. Epipleurse entire, as broad 

 at apex as at middle. Intercoxal process of abdomen moderate, rounded at tip. Anterior 

 tibia; slightly dilated, outer apical angle distinct, external edge with a few small teeth, 

 spurs rather large;. 



D. punotatus, Leo., loc. oit. 



A small, elongate; oval, black species, with the head and thorax and elytral stria? 

 coarsely punctured. The elytra have eight stria; but no scutellar stria. In the specimens 

 in my possession the suture defining the epistoma is quite distinct, the line being darker 

 and smoother than the rest of the front. The epistoma is narrow, short and semilunar 



Length .10-15 inch. Found rather abundantly under pine bark, over our whole 

 country. 



GNATHOCBRTJ8, Thunb. 



Gnathocerus, Thunberg., Act. Holm. 1814, p. 47. 



Mentum small, trapezoidal. Maxillary palpi elongate oval, very obliquely truncate at 

 tip. Epipleuree short. Base of thorax rather distant from base of elytra, Head with 



AMl'UU. PHILOSO. 800 VOL. XTV. — 92 



