178 HETEROMERA. 
7. Arrhenoplita distans. (Tab. VIII. figg. 8,3; 8a, head from the front.) 
Oblong ovate, subparallel, strongly convex, castaneous, very shining. Head broad; in the male almost 
impunctate, broadly excavate anteriorly, the epistoma with a small rounded prominence on each side in 
front, the antennary orbits swollen and raised, the eyes very widely separated, the intraocular space 
armed on each side with a stout straight erect horn (the broad space between flat), the vertex not 
impressed; in the female finely and distantly punctured, broadly excavate anteriorly, the epistoma 
slightly swollen, and sometimes with a small prominence on each side as in the male, the front broadly 
flattened (the depression limited behind by an oblique extension of the small rounded prominence placed 
on each side of the broad intraocular space); antenn with the eight outer joints widened, ferruginous 5 
prothorax transverse, the base and apex bisinuate, the anterior angles prominent, the hind angles broadly 
rounded, strongly’ margined at the sides, the sides in the male rounded, in the female straighter and 
widest a little beforé the base, moderately convex (more strongly and transversely in the male), the 
surface finely and sparingly punctured; scutellum large, subtriangular; elytra with regular rows of 
shallow, distantly placed, coarse punctures, the interstices flat, sparingly and finely punctured, the apices 
slightly acuminate; legs and antenne pale ferruginous ; beneath shining, light castaneous, sparingly and 
finely punctured ; epipleurs not extending to the apex of the elytra. 
Length 52-63 millim. (¢ @.) 
Hab. Mexico, Cordova (Sal/é). 
Five examples. This shining castaneous species may be known from its allies by the 
erect cephalic horns of the male being separated by a very wide, smooth, and flat space ; 
the female by the broad flattened frontal depression, limited behind by an oblique 
extension of the small prominence placed on each side just within the widely 
separated eyes. 
8. Arrhenoplita obsoleta. 
Elongate oval, subparallel, strongly convex, varying in colour from castaneous to black, shining. Head in the 
male rather coarsely and closely punctured, broadly excavate anteriorly, the: epistoma swollen, sharply 
defined, and usually armed on each side in front with a minute rounded prominence, the intraocular space 
with a small rounded prominence on each side just within the eye (much as in the females of some of the 
allied species) and often with a small impunctate space in the middle; in the female more coarsely and 
closely punctured, transversely excavate anteriorly, the epistoma less swollen than in the male; antenne 
with the eight outer joints widened; prothorax transverse, widening from the rounded anterior angles to 
beyond the middle, thence rounded to the base, the apex almost straight, the base bisinuate, the surface 
rather coarsely and not very finely punctured; elytra with regular rows of closely placed, rather coarse, 
shallowly impressed punctures, the interstices rather coarsely and sparingly punctured and with traces of 
shallow transverse wrinkles; legs and antenne light ferruginous; beneath shining, closely, confluently,, 
and irregularly punctured. 
Length 33-5 millim. (¢ 9.) . 
Hab. Mexico, Cordova, Vera Cruz (Sallé), Jalapa (Hoge). 
Many examples. The head in the male is formed much as in the female of 
A. amazonica, ¥. Bates, an insect closely allied to the present species; the female 
does not differ greatly from the male. In A. obsoleta we have but a very slight 
development of the male cephalic armature, the horns being represented by very small 
tubercles, such as we observe in the. females of most of the other species of the 
genus. 
