76 NORTH AMERICAN 



first slowly, then more rapidly in width posteriorly, first distinctly wider 

 than the contiguous elytra; surface broadly convex, coarsely, closely, and 

 variolately punctulate ; transverse carinae not cusped. Legs rather long 

 and slender, dark piceous-brown ; first joint of the posterior tarsi four-fifths 

 as lung again as the second, second as lung as the third and fourth together, 

 fourth very short. Under surface of the abdomen piceous-black, very finely 

 and closely punctulate. 



Mah . — Posterior edge of the fifth ventral segment just perceptibly bilobed, 

 arms extremely divergent ; sixth segment strongly bilobed at apex, emargi- 

 nation twice as wide as deep ; seventh segment very narrow, truncate at the 

 apex. 



Female. — Sixth segment broadly and triangularly produced; angle very 

 prominent. 



Length 2.6-3.0 mm. 



Garland, Colorado, 7 ; Veta Pass, Colorado, 2 ; British Columbia. 4. 



A specimen from British Columbia is singularly deformed by an 

 enlargement of the left eye. The identification of this species is due 

 to Mr. Fauvel, and as it is a somewhat rare European species, its 

 occurrence on the western side of our continent is rather remarkable. 

 In one specimen the apical joint of the left antenna is deeply exca- 

 vafed nearly throughout its entire length and width, as if the surface 

 had been accidentally crushed in. The probable cause of this condi- 

 tion, which is of somewhat frequent occurrence in the species of this 

 genus, may perhaps lie in the internal structure of the terminal joint. 

 The interior fibres of the joint on drying contract, drawing in the 

 weakest portion of the surface in such a way as to leave a deep ex- 

 ternal concavity; as it is always found on the under side, we must 

 presume that, at this point, the walls of the joint are weakest, or most 

 firmly attached by nerve fibres to the interior tissues. It would be 

 interesting to know whether the condition is ever observed in speci- 

 mens recently taken. 



Subdivision B. 

 Group II. 



This group consists of a very limited number of species of peculiar 

 appearance. They are of rather small size, robust, and somewhat 

 strongly depressed ; the elytra are large, and the humeral angles 

 prominent ; the head is small. The elytral suture is, in all eases, at 

 least one-half longer than the pronotum. 



The species which seem worthy of adoption are five in number; 

 they are peculiar to the regions west of the Rocky Mountains, and 

 may be tabulated as follows : — 



