BEROSUS. | 79 
Volvulus, but very improperly. Berosus has the front tibie slender and linear, and 
deeply grooved externally for the accommodation of the tarsi when retracted, a character 
of itself amply sufficient, even if we leave out of consideration the other numerous 
points of distinction, to distinguish it from its heterogeneous associates. As thus 
limited, Berosus remains an extensive genus, with fully fifty described and a large 
number of undescribed species, distributed over most of the earth’s surface, but appa- 
rently more attached to the warmer regions. The species form a most difficult study, 
owing to their great resemblance and the absence of conspicuous differences in form 
and colour and sculpture. North America has sixteen species; and these have been 
well characterized by Leconte, and more recently by Horn (Trans. Am. Phil. Soe. xiii. 
p- 118 e¢ seqg.). The latter author has used some valuable characters for forming sections 
in the genus, one of which, however, should be abandoned. 
The Central-American species here enumerated form three groups, viz. :— 
1. Elytra spinose at extremity. B. truncatipennis, B. griseus, and B. salvini. 
2. Elytra unarmed at apex; basal ventral segment without carina, except between 
the coxe. B. puncticollis, B. infuscatus, B. falcatus, B. flavicornis, B. meai- 
canus, and B. metalliceps. 
3. Elytra unarmed at apex; basal ventral segment with a well-marked carina 
extending along nearly all the length of the middle. J. gracilipes and 
B. merens. 
1. Berosus salvini. (Tab. III. fig. 1.) 
Major, supra testaceus, in elytris fusco-maculatus, capite aneo; thorace dense fortiterque punctato, medio 
metallico-bivittato, utrinque fusco maculato; elytris wqualiter sat profunde striatis, interstitiis crebre 
fortiterque punctatis, apicibus spinosis anguloque suturali evidenter acuminato; corpore subtus nigro, 
prothoracis lateribus late testaceis ; antennarum basi, palpis pedibusque testaceis, femoribus basi nigris, 
tibiis intermediis et posterioribus versus apicem cum tarsis nigricantibus. 
Long. 33, lat. 14-13 lin. 
Hab. Mexico, Oaxaca (Hége), Guanajuato (Dugeés, coll. Sallé), Puebla, Toluca (Sallé) ; 
GUATEMALA, Guatemala city 5000 feet (Champion and Salvin), San Joaquin (Champion). 
This is a remarkable species, the size being larger than usual, and the upper surface 
nearly dull, with coarse close sculpture. The spots on the elytra are very large, and 
sometimes suffused so as to make the surface appear nearly entirely dark. The tooth 
at the apex of each wing-case is slender and moderately long, and the suture, though 
not spinose, is distinctly prolonged and acute. ‘The male has the basal joints af the 
front tarsi much dilated; the fifth ventral segment has in the middle a rather broad 
emargination, so that it forms a prominent tooth on each side; and the middle part of 
the base of the emargination is a little produced backwards, and in front of this the 
surface is strongly elevated and compressed so as to form a rather short but prominent 
carina; the fourth segment bears in the middle behind a small tooth. The female is 
