120 HETEROMERA. 
the sides behind the eyes, and largely developed, as wide as the prothorax, the eyes quite small and not 
prominent, the antenne ferruginous and stout; prothorax longer than broad, convex, the sides much 
rounded in front and moderately constricted behind, the hind angles very prominent, the base strongly 
margined, the disc transversely depressed before the middle and also before the base, the surface irregularly 
and rather sparsely punctured, a smooth, narrow, longitudinal space on the middle of the disc impunctate, 
this space deeply impressed towards the base; elytra coriaceous, long, widest beyond the middle, depressed 
on each side at the base in the centre, closely, shallowly, and finely punctured, with three vague coste 
and several very irregular shallow longitudinal grooves extending from the base nearly to the apex, the 
suture also a little raised; beneath finely and closely punctured and pubescent; legs fusco-ferruginous ; 
fifth ventral segment unemarginate. 
Length 143 millim. (2.) 
Hab. Guarema.a, Tepan 6000 feet (Conradt). 
One example. Larger and broader than the largest examples of the corresponding 
sex of D. cephalotes ; the head and thorax much less closely punctured, the latter with 
the base more strongly margined and the hind angles more extended; the eyes not so 
prominent; the elytra more shining, more strongly (though very shallowly) punctured, 
and with shallow longitudinal grooves and vague coste extending from the base nearly 
to the apex. 
** Head largely developed in the male (at least in D. mexicanus), normal 
in the lowest development of the female. 
5. Ditylus mexicanus. (Tab. V. fig. 24, 3.) 
Elongate, depressed, finely pubescent, blackish-violaceous; the head and prothorax violaceous or bluish, and 
slightly shining, the latter with a red spot on each side in front, or with the sides rather broadly, and the 
disc also red; the elytra very opaque. Head as wide as the prothorax, a little dilated on each side behind 
the eyes—in well-developed males longer and broader, with the sides behind the eyes more extended 
(reaching outwardly as far as the eye itself), and more abruptly narrowed behind,—very finely and densely 
punctured, the eyes small, the antenne black; prothorax about as long as broad, the sides strongly 
rounded anteriorly and much constricted behind, the hind angles acute, the disc with a deep (or shallow) 
transverse depression in the middle before the base, a shallow one in front, and two more or less distinct 
rounded depressions on each side (one before, the other behind the middle), the surface densely, finely, and 
irregularly punctured, the punctures in the depressions obliquely confluent, an irregular, narrow, longi- 
tudinal, slightly raised space on the middle of the disc impunctate; elytra moderately long, subparallel in 
their basal half, broadly flattened on the disc, very minutely and densely punctured, the punctures 
connected by oblique scratches, with one or two vague coste down the middle of the disc, and one near 
the side (the latter extending from below the shoulder to the apex, and limiting the flattened portion 
laterally), the suture also a little raised; beneath finely and densely punctured and pubescent, violaceous, 
the prothorax and venter sometimes reddish ; legs black; fifth ventral segment arcuate-emarginate in the 
middle in the male, rounded in the female. 
Length 73-103 millim. (¢ 2.) 
Hab. Mexico (Sallé), near the city (Hoge). 
Five examples, two males and three females. This species is distinguished by its 
depressed form from all others of the genus yet described. The elytra, when viewed 
under a strong lens, are obliquely strigose. D. meaicanus is apparently allied to 
D. bicolor and D. cyanipennis, Horn. 
