52 STUDIES IN NORTH AMERICAN MKMBR AC! I ).E 



green band and the head is black with a transverse greenish 

 band below the ocelli that is extended upward along the inner 

 margin of the eyes; the costal nervure is also black. This 

 would indicate a transition toward semicrcma, but judging from 

 the material I have seen it may be sufficiently distinguished by 

 its smaller size, more polished surface and the shorter and 

 less decurved posterior process of the pronotum. 



Genus Micrutalis Fowler. 



If we admit this genus as distinct from the foregoing we 

 must distinguish it by the four apical areoles in place of five 

 and the very obscure venation of the elytra, and so distinguished 

 it must embrace our large northern Acatalis dorsalis Fitch, as 

 well as the smaller southern and western forms allied to 

 calva. Dorsalis is intermediate between these genera not only 

 in its large size but in the fact that the outer apical areole, 

 which in this genus is formed by the coalescence of the two 

 areoles between the terminal and costal, has at times a minute 

 fifth areole at the apex of the costal. This indicates that this 

 large areole is not formed by the atrophy of the nervure nor- 

 mally dividing the two areoles found there in A cut alts but by 

 the crowding of this nervure against that forming the apex of 

 the costal areole. In the smaller and more typical species of 

 this genus the stylated terminal areole is very small and at 

 times entirely wanting; leaving then but three apical areoles. 

 Our described species may be placed as follows: 



Size large, 4-5 mm. ; dorsum usually with a brown or black 



discal spot, 1, dorsalis Fitch. 



Size small, less than 4 mm., 1. 



1. Minute, 2^ mm.; head yellow with base and apex black ; 



inhabits Arizona, 6, parva Godg. 



-. A little larger, 3-4trmi., 2. 



2. Pacific coast species with the apex of the pronotum more 



obtuse; length 3 mm., 3. 



Eastern species with the apex of the pronotum more slen- 

 der and acute; length 3/4-4 mm., 4. 



3. Pale, the dorsum sometimes marked with a brown median 



line which may be expanded between the humeri and 

 before the apex, 4, occidentalis Godg. 



