452 | HETEROMERA. 
have been referred to this genus, but very many of these will have to be separated 
when the numerous tropical forms are more’thoroughly investigated. 
1. Antenne rather stout, often more or less serrrate in the male ; species moderate 
im size. 
* Siath ventral segment in the male short (hidden by the fifth), its apical margin 
truncate and without lateral lobes; anterior tarsi similar in both sexes. 
1. Cistela nigricornis. (Tab. XX. figg. 22, 22a, 3.) 
Oblong ovate, broad, slightly convex, piceous-brown, sometimes of a lighter and more reddish tint, opaque, 
thickly clothed with ashy pubescence. Head closely and finely punctured ; eyes large and rather narrowly 
separated in the male, smaller and more distant in the female ; antenne black or piceous (rarely fusco- 
ferruginous), lighter at the base—(¢ ) reaching to beyond the first third of the elytra, joint 3 short, not 
very much longer than 2, joints 4-10 flattened and subserrate within, ( 2 ) shorter, joint 3 longer (though 
not so long as 4), joints 4-10 narrower and less dilated at their inner apical angle; prothorax very short, 
strongly transverse, the sides rounded and narrowing from a little before the base, the hind angles rather 
obtuse, the basal fovee almost obsolete, the base strongly bisinuate, the surface finely and very densely 
punctured ; scutellum finely and closely punctured ; elytra a little rounded at the sides, shallowly striate 
throughout, the strie with fine, shallow, closely-placed punctures, the interstices flat or very feebly convex 
and very finely and closely punctured, the surface not quite so dull as that of the prothorax; beneath 
finely and closely punctured, the metasternum more sparsely so, the latter with a deep longitudinal groove 
in the middle; legs rather slender, brownish-piceous or obscure ferruginous. The tarsi similar in both 
sexes, their antepenultimate joint somewhat produced beneath. 
g. Abdomen with a short but hidden non-lobed sixth ventral segment; the central sheath laterally com- 
pressed, the apex slightly hooked above. 
Length 53-72 millim. ; breadth 3-4 millim. (3 9.) 
Hab. Mexico, Ventanas in Durango, Chilpancingo, Jalapa, Almolonga, Tapachula in 
Chiapas (Z/ége), Oaxaca, Guanajuato, Tehuantepec (Sallé); Nicaragua, Chontales 
(Belt); Cosra Rica, Cache (Rogers) ; Panama, Volcan de Chiriqui 3000 feet (Champion). 
Many specimens from Mexico and one only from each of the other localities. This 
is apparently the commonest of the allied forms in Mexico. In some male examples 
the third joint of the antenne is rather longer than in others; in the single male 
from Nicaragua (doubtfully referable to the same species) the antenne are ferru- 
ginous and more distinctly serrate, and the metasternum is more sparsely punctured. 
Immature abraded examples have a rather different facies, owing to their less opaque 
surface, &c. 
2. Cistela zunilensis. 
Oblong ovate, rather narrow, fusco-testaceous or obscure reddish-brown, dull, thickly pubescent. Head finely 
and closely punctured; eyes large and rather narrowly separated in the male, smaller and much more 
widely separated in the female; antenne fusco-testaceous, often lighter towards the base—(¢) long, 
reaching fully to the middle of the elytra, joint 3 short, not much longer than 2, joints 4-10 flattened and 
moderately serrate within, (2) shorter, narrower, and more slender, joint 3 much longer (nearly as long 
as 4), joints 4-10 elongate triangular in shape; prothorax very short, strongly transverse, the sides 
rounded and narrowed from a little before the base, the hind angles subrectangular, the basal foves 
