270 GEO. H. HORN, M. D. 



Group XII, crenulata. 



The species of this group are of moderately large size, the upper 

 surface hairy in different degrees. The clypeus is always emarginate, 

 although feebly in several species, the margin narrowly reflexed. 

 Last joint of maxillary palpi fusiform or cylindrical impi-essed in 

 but one species. Antennae 10-jointed, the male club not so conspicu- 

 ously longer than that of the female, as is usual in the genus ; the 

 lateral margin of the thorax may be either entire or crenate ; pectus 

 with long hairs in some species, nearly naked in others. Abdomen 

 moderately closely punctured over the entire surface. Claws with a 

 strong, acute, median tooth alike in both sexes in crenulata, rubigi- 

 nosa, (emula, arcta and alb ina; small and intramedian in the male, 

 but stronger and more nearly median in the female, parvldens and 

 vetula; posterior tarsi shorter in the female in parvldem alone. . Spurs 

 of posterior tibise free in both sexes. 



Thevestiture of the surface presents two forms — that in which the 

 pubescence is uniform and recumbent, and that in which there are 

 longer erect hairs intermixed. In parvldens, however, the erect hairs 

 are not very obvious, except on the thorax. The erect hairs where 

 they occur have a tendency to form a serial arrangement along the 

 suture and the lines of the discal costte and are always more abun- 

 dant and longer in the females than in the males. One species has 

 conspicuously long erect hairs on the elytra {vetula). 



One of the species {crenulata) has a wide distribution, the others 

 seem restricted and rather local. They are as follows : 



Pubescence of upper surface flue and recumbent, without any intermixed erect 

 hairs. 



Form robust, front and clypevrs coarsely punctured. 56. ;einiila. 



Form cylindrical, punctuation extremely fine and dense 57. arcta. 



Pubescence of upper surface intermixed or erect. 



Margin of thorax strongly crenate 58. creiinlata. 



Margin of thorax at most feebly serrate behind the middle. 



Pubescence of surface white 59. albiiia. 



Pubescence yellowish or brownish. 



Upper surface with very long erect hair; palpi distinctly impressed ; club 



of antennfe % and 9 equal. 60. vetula. 



Erect hair moderate; last joint of palpi not impressed; antennal club 

 % long. 



Thorax shining, punctures not dense 61. rubiginosa. 



Thorax somewhat opaque, punctures close, often dense. 



62. parvideiis. 



