60 J. L. LECONTE, M. D. 



Texas; Mr. Bclfrapfe. Female unknown. Varies of a blackish 

 color with the occiput anJ tip of abdomen testaceous. After examin- 

 ing the type of Mastlnocerua, in the Paris Museum, I see no reason 

 for .separating this as a distinct genus. In the Chilian type the last 

 joint of the antenncc has been broken off, and the 10th joint, by want 

 of sufficient care has been regarded as the last joint, which has been, 

 therefore, absurdly described as bifurcated, a form which I am. free 

 to say that our present knowledge leads us to 'believe does not exist 

 in Coleoptera. In the Texan species above described the antennae 

 are 11-jointed, the 1st joint as long as the 'lA and 3d, which are sim- 

 ple, the j)ints -1 — 10 slightly increasing in length, each with two 

 long basal hairy cylindrical processes, about three times as long as the 

 joint itself ; 11th joint simple, as long as the branches of the lOth 

 joii.t ; maxillary palpi nearly as long as the head, last joint large, 

 moderately dilated with the palparium elliptical; eyes large, finely 

 gninulated. The seventh ventral segment is eniarginated almost to the 

 base ; the last dorsal is subtruncate or broadly rounded, with two 

 shallow longitudinal furrows. 



SIL,IS Charp, 

 The following table will enable the species of this genus to be easily 

 distinguished; 8 and 9 miy be perhaps variations in color of one 

 species. 



' A. — Base of prothorax broadly rounded, sides excavated into a deep round 

 cavity near the base; both angles of the excavation acute; ante basal ap- 

 pendage acute, spinifonn I. »»pinigera. 



B. — Base of prothorax lobed, excavation of hind angles partly basal, angles 

 therefore not very distinct, though acute, anterior margin of excavation 

 sinuate with two prominent rounded angles; ante-basal appendage 

 acute, spinlform, directed obliquely backwards. 

 Basal excavations of prothorax moderate, (color black, disc of prothorax yel- 

 low) .• 2. difticiiis. 



Basal excavations of prothorax larger (elytra and prothorax pale). 



3. flavida. 

 C. — Base of prothorax lobed, deeply foveate, inside of the hind angles, which 

 are therefore more prominent and acute ; incisure near the base moder- 

 ately deep, with the anterior angle rounded; ante-basal process com- 

 pressed, rounded at tip. 

 Basal impressions of prothorax very deep, hind angles strongly cariuated 

 (upper surface pale). 



Incisure of hind angle deep, appendage straight 4, cava. 



Incisure of hind angles broad, appendage curved „ 5. pallida. 



Basal impressions of prothorax much smaller; hind angles feebly cariaaled ; 

 (black, prothorax more or less yellow). 



