162 HETEROMERA. 
testaceous, the former with an oblong patch on the vertex (obsolete in one example), and the latter with 
a median vitta and a rather large spot on each side in front, black; the elytra brownish or fuscous, and 
usually with the suture very narrowly paler, the extreme base often stained with piceous. Head very 
closely and finely punctured, the epistoma, and often a narrow space along the middle, smoother, the tips 
of the mandibles, the eyes, and the palpi (usually) black ; antenne black, or black with the outer four or 
five joints testaceous, or testaceous with joints 1-3 piceous, the third joint the length of the first, the 
eleventh strongly constricted at the middle; prothorax convex, much longer than broad, the sides very 
strongly rounded anteriorly, abruptly constricted at the middle, and converging thence to the base, the 
disc depressed and canaliculate in the middle towards the base, and sometimes with a narrow smooth 
central space, and with a bare impunctate spot on either side at the lower inner limit of the lateral 
marking, the base feebly emarginate in the middle, the surface very closely and finely punctured; elytra 
scabrous-punctate, and sometimes with traces of one or two raised lines on the disc; beneath densely and 
finely punctured, piceous or piceous-brown, the prothorax testaceous; legs variable in colour—piceous 
with the basal half of the femora testaceous, or fusco-testaceous with the knees piceous. 
Length 8-10 millim. (3 @.) 
Hab. Mexico, Pinos Altos in Chihuahua (Buchan- Hepburn), Presidio (Forrer), Iguala 
and Chilpancingo in.Guerrero, Oaxaca (Hége); Nicaracua, Chontales (Belt). 
Eight examples from Mexico and one from Nicaragua, the latter agreeing perfectly 
with the others. Closely allied to and much resembling some of the varieties of 
O. cana; the thorax, however, is more regularly convex, more strongly rounded at the 
sides anteriorly, and has the lateral spot placed near the anterior angles, instead of at 
or near the middle as in 0. cana. The thorax is similarly marked in all the examples 
before me, and the insect shows very little tendency to variation. An allied undescribed 
species from Venezuela is known to me. A specimen from Presidio is figured. 
23, Oxacis schistacea. (Tab. VII. fig. 21.) 
Hypasclera schistacea, Kirsch, Berl. ent. Zeitschr. 1866, p. 211". 
Hab. Panama, Matachin (Thiéme).—Cotoms14, Bogota}. 
An example of a species of this genus captured by Dr. O. Thiéme in July 1877 along 
the line of the Panama railroad, and kindly given us by Dr. Sharp, agrees very nearly 
with the description of Hypasclera schistacea, Kirsch ; it differs, however, in some minor 
details and in being smaller in size. The unicolorous pale blue colour (which is much 
obscured by the dense ashy pubescence) and testaceous legs distinguish this species from 
the other allied forms. It is perhaps advisable to give a description of the Panama 
insect :— 
Elongate, narrow, subopaque, above and beneath pale ceruleous, densely clothed with fine ashy pubescence. 
Head densely and minutely punctured, the labrum and the greater part of the mandibles testaceous, the 
apices of the latter and the eyes black, the mandibles sharply pointed at the apex; palpi piceous, the last 
joint of the maxillary pair elongate-triangular and with its inner side rather longer than the apical side ; 
antenne (3) very long, joint 1 about as long as 3, 11 strongly constricted at the middle, fusco-testaceous, 
the basal joint testaceous ; prothorax much longer than broad, as wide as the head, rather convex, the sides 
a little rounded anteriorly and gradually converging from before the middle to the base, the disc canali- 
culate in the centre behind and with a shallow oblique depression on either side anteriorly, the surface 
densely and minutely punctured; elytra less densely punctured than the head and prothorax, and with 
