NORTH AMERICAN COLEOPTERA. 99 



While the first division is of more nearly the usual construction in 

 the genus it nevertheless presents a slight diiference worthy of mention, 

 as it may assist in the recognition of species when only females are at 

 hand. If we imagine a quadrangle formed by drawing a line across the 

 front of the eyes, another parallel to it across the basal constriction of the 

 head, and two others along the sides, it will be observed that in species 

 17-23 (also 16 of Series B) the quadrangle thus formed is always 

 broader than long, while in all the species of Series A the quadrangle is 

 either squai'e or longer than wide. 



The last three species of the present series form a group by themselves 

 characterized by the form of the head, the occurrence of which is pre- 

 dicted by that of ohli'qunm of Series A. 



The following species occur in our fauna : 



Head parallel, or soinewhat arcuate behind the eyes and abruptly narrowed ; hind 



angles distinct 2. 



Head obliquely narrowed from the eyes to the neck ; the hind angles notdistinet.fi. 



2. — Large species, pieeous, almost black 3. 



Small species, brown or rufo-testaceous 5. 



3.— Sides of head strongly arcuate and broader behind the eyes.. I 7. tiiBniduni. 



Sides of head nearly parallel, not wider behind the eyes 4 



4. — Last ventral % deeply narrowly incised IS. califoi'iiiciiin. 



Last ventral % triangularly emarginate l'.K pullipes. 



5. — Head very coarsely, deeply and closely punctured 21. piLsillniii. 



Head sparsely punctured. 



Dark brown, head and thorax a little paler 20. properiiiti. 



Pale rufo-testaceous, shining. 



Median smooth space of thorax well defined and somewhat elevated pos- 

 teriorly ; punctuation of elytra very distinct 23. Iopi<liini. 



Median smooth space not well defined, flat ; punctuation of elytra finer 



and rather indistinct 22. iiHC'tiiin. 



(5. — -Head with extremely few pum-tures 7. 



Head smooth in front, normally puuctured posteriorly 8. 



7. — Pieeous, elytra rufo-testaceous, coarsely deeply, not closely punctate. 



24. cribratum. 

 Anterior portion of head, thorax, two basal and two apical segments black, 

 surface elsewhere reddish yellow; elytra sparsely coarsely punctate. 



26. serpeiitiiiiim. 



8. — Color black, elytra reddish yellow with a broad sutural stripe not reaching the 



apex; punctuation of elytra close 25. sellatliui. 



IT. C tiiinidiini Lee — Pieeous, almost black, elytra somewhat paler, shin- 

 ing, sparsely pubescent. Antennae rufo-testaceous, nearly as long hs the head and 

 thorax, third joint distinctly longer than the second. Head black, shining 

 broadly oval, wider behind the eyes, the sides arcuate, hind angles broadly rounded, 

 surface coarsely, deeply and closely punctate. Thorax narrower than the head, 

 about one-fourth wider than long, sides parallel, median smooth space well de- 

 fined, the punctures finer than those of the head, closely placed near the smooth 



