24 MEMOIRS ON THE COLEOPTERA 



and cupreous, with very dense white hairs, glabrous only along the middle, 

 more broadly on the sterna; eyes large and prominent; labrum (cf) 

 short, with a single small acute medial tooth; prothorax much narrower 

 than the head, nearly as long as wide, convex, parallel, with strongly 

 and evenly rounded sides; elytra subparallel, acutely ogival at tip, white 

 throughout, except a cupreous sutural region broad at base, narrowly 

 ending at two-thirds, its lateral outlines bilobate; white area minutely 

 and sparsely, the cupreous strongly and closely, punctate; serrulation of 

 the apices very fine, the sutural spine strong and acute; legs very slender, 

 cupreous and green. Length (c?) 9.8 mm.; width 3.4 mm. New Mexico 

 (Santa Rosa), Knaus. 



This is a very interesting form, much smaller in size than togata 

 and of very different ornamentation. 



In the marginata group, amnicola should be given specific rank 

 and mundula attached thereto as a subspecies or variety. 



Cumatilis and collusor are merely subspecies of rufiventris, but 

 hentzi is a different species, allied to i6-punctata and sonorana but 

 distinct from either. Beckeri W. Horn, is allied to sonorana but is 

 smaller, more slender and much more brilliantly cupreous on the 

 head and prothorax; I have in my collection a good series of five 

 examples taken by Townsend in Chihuahua. 



