454 PROCEEDLNGS OF THE NATIONAL. MUSEUM vol. loi 



same group, which he distinguished by the presence of high, raised, 

 conical, dorsal tubercles and the cupreous metallic color. In a foot- 

 note in the same revision, the author ^ indicates the differences in the 

 form of the antennae and tarsi of the three species, which he states 

 are so closely allied otherwise that these differences must not be taken 

 into account in the grouping of the Chlamisus species. 



However, study of the three above-mentioned species shows that 

 they are only apparently related to each other. I believe, for example, 

 that C. hirtus is worthy of a separate genus or subgenus based on the 

 following characters: The pubescent dorsal surface; the form of the 

 tarsal claws; and the shape of the male genitalia, which are different 

 from those found in any other species of Chlamisus. The form of the 

 male genitalia of spinosus is also very peculiar and not like that of 

 any other species of the genus, and this seems sufficient reason to 

 exclude that species also from relationship with hispidulus. 



Chlamisus hispidulus, with its allied forms that are dealt with in 

 this paper, approaches C. gibbosus, the genotype as designated by 

 Jacoby,^ and other North American species of Lacordaire's eleventh 

 group. These species may be considered to belong to the typical 

 group, although there must be a reduction in the heterogeneous 

 species that now make up the genus. 



Chlamisus hispidulus presents a number of closely allied forms that 

 may be separated by the key. The systematic range of all these 

 forms is not always clear, and some of them are perhaps no more than 

 subspecies of different geographic distribution. Except for (7. 

 hispidulus llajtamaucanus, for which subspecific relationship can be 

 established, it has seemed better to consider them all as different 

 species, at least for the present. 



KEY TO THE SPECIES OF THE CHLAMISUS HISPIDULUS GROUP 



1. Pygidium shagreened; its surface subopaque, not more shining than rest of 



abdomen; pronotal and elytral tubercles obtuse; in former it is not possible 

 to distinguish four conical spines; elytral tubercles more or less united and 

 ridge-shaped, not like independent cones; length 3.8 mm., 2.6 mm. (southern 



Bolivia) siraillimus Monr6s 



Pygidium smooth, with some superficial punctures, more shining than rest 

 of abdomen 2 



2. Pronotum with a broad median groove, on both sides of which there are two 



conical tubercles, more or less pointed but always very distinct 3 



On each side of median pronotal groove an elongated raised area, top of which 

 is surmounted by a continuous edge somewhat depressed in its middle; 

 elytral tubercles moderately developed; more elongate shaped than in the 

 following species; length 4 mm., breadth 3 mm. (central and western Argen- 

 tina) hispidulus llajtamaucanus, new subspecies 



« Lacordaire, Monographie des Coleopteres * * * , Phytophages, vol. 2, p. 697, 1848. 

 » Fauna of British India: Coleoptera, Chrysomelidae, vol. 2, p. 271, 1908. 



