128 MEMOIRS ON THE COLEOPTERA 



becomes notably obtuse and rounded at tip ; the form of the clypeus 

 is therefore much less important as a generic character than the 

 structure of the mentum and certain other more general characters. 



Mimeoma n. gen. 



The chief characters separating this genus from the preceding 

 are the widely separated middle coxae, with flat subglabrous de- 

 scending interspace, virtually glabrous under surface of the body, 

 laminate and not expanded post-coxal process of the prosternum 

 and the nature of the female sexual characters. The antennae are 

 still smaller than in Ancognatha and the clypeal suture, though 

 fine, is evident throughout the width, sinuous medially but not at 

 all deeper at the sides; the surface of the head, also, does not rapidly 

 ascend above the upper margin of the eyes. The body is very 

 much smaller in size than in any known Ancognatha. In the 

 female the sides of the elytra are much swollen behind the middle, 

 the general swelling bearing a rounded smooth tumor at apical 

 two-fifths of the elytra, the edge below the swelling narrowly and 

 gradually explanate, with slightly thickened bead. The type is 

 the Cyclocephala maculata of Burmeister, occurring in Cayenne 

 and in the Amazon regions. 



Diapatalia n. gen. 



The type of this genus is a small species, closely resembling a 

 narrow Cyclocephala to external view, in habitus and ornamentation, 

 but having a strongly sinuate clypeus and still more conspicuous 

 female sexual characters; the mento-ligular plate is rather convex 

 parallel, evenly rounded at the sides, deeply excavated at tip, which 

 is not laterally contracted though following the curvature of the 

 sides to the apex, and the apex is angularly sinuate between the 

 short and sharp but unprolonged angles; at some distance from 

 each side of the plate there is a regular line of coarse punctures 

 bearing inconspicuous erect hairs. The under surface of the body 

 is glabrous, the intermesocoxal surface rather wide, flat and 

 anteriorly sloping, and the erect antero-posteriorly compressed 

 post-coxal process of the prosternum is also as in Mimeoma. Ad- 

 ditional characters are alluded to in the following description of 

 the only known species: 



