134 MEMOIRS ON THE COLEOPTERA 



Cyclocephala Latr. 



As here restricted, this genus is composed of a considerable 

 number of species occurring exclusively in the tropical regions of 

 the American continents, and they all have the posterior edge of 

 the pronotum minutely and completely beaded and in a singularly 

 constant fashion, giving an appearance of a duplex edge, which 

 character is shared also by Diapatalia, Spilosota, Halotosia and 

 Aclinidia, but is completely wanting in Ochrosidia, Diachromina 

 and Homochromina, although the last three may have a feeble 

 beading occasionally toward the sides of the base; it is the constant 

 entirety of the fine bead throughout the width that is so conspicuous 

 and characteristic a feature of the present genus and the first four 

 just mentioned. Cyclocephala may be separated into a number of 

 marked subgenera, of which the three following can be defined at 

 this time: 



Anterior tibiae of both sexes strongly and subequally tridentate; body 

 moderately convex, the elytral ornamentation obliquely lineate 

 nearly throughout the length, the pronotum never vittate; marginal 

 modification in the female feeble, simple and confined to a slight 

 thickening and very narrow deplanation of the edge; tarsi notably 

 short and slender in the female; scutellum ogival, rather wider than 

 long Group I 



Anterior tibiae of the male simply bidentate, the upper of the usual three 

 teeth rarely visible as a very feeble vestige, normally tridentate in 

 the female; tarsi notably elongate in both sexes; scutellum more 

 pointed, slightly elongate 2 



2 Body having the normal convexity of the tribe; male with the first 

 four abdominal segments and the sixth equal in length and very 

 much shorter than the fifth segment; elytra with ornamentation 

 consisting of two subbasal and one post-median black spots, some- 

 what as in the following group; pronotum not vittate. . . .Group II 



Body of more feeble convexity, somewhat as in Diapatalia and similarly 

 with very conspicuous marginal modifications of the female elytra; 

 pronotum with two black vittae, the elytra with various modifications 

 of two subbasal and one post-medial black markings; male with the 

 abdomen similar in the sexes and with the segments subequal among 

 themselves Group III 



The typical species of these three groups, considered in order, are 

 complanata Burm., an apparently undescribed species from Mexico, 

 and signata Drury. Stictica, which belongs to the third group, 

 was widely separated by Burmeister from its allied forms and placed 

 near lucida, which it does not in the least resemble, merely because 



