ERXTAS.—PROSTENUS. 461 
elytra relatively shorter, shining, cyaneous in tint, and more finely and much more sparsely punctured ; 
the rest as in E. violaceipennis. 
Length 11 millim.; breadth 53-51 millim. ( 2.) 
Hab. Panama, Bugaba, Volcan de Chiriqui (Champion). 
Two female examples. This insect apparently replaces EL. violaceipennis in the State 
of Panama; but, on account of the above differences, Iam unable to treat it as a 
variety or local form of that species. 
PROSTENUS. 
Prostenus, Latreille, Fam. nat. du Régne anim. p. 377 (1825) ; Lacordaire, Gen. Col. v. p. 513 
(1859). 
Xystropus, sect. Mecocerus, Solier, Ann. Soc. Ent. Fr. iv. p. 241 (1835). 
This interesting genus contains a number of species in Tropical and Subtropical South 
America, very few of which have been described as yet; one inhabits the southern 
portion of our region. The antenne have their outer joints very large and much 
flattened, often foliaceous or exceedingly broad; the femora are clavate towards the 
apex; and the intercoxal process is very broad. ‘The thorax varies in shape in the 
different species from transverse to as long as broad. 
1. Prostenus panamensis. (Tab. XXI. fig. 6, ¢.) 
Elongate, rather convex, piceous-brown with a bronzy tint, the upper surface opaque, more or less olivaceous, 
and clothed with long and erect scattered hairs, and also somewhat thickly pubescent. Head coarsely 
and rugosely punctured; eyes transverse, convex, and widely separated ; antenne metallic violaceous or 
cupreo-violaceous, very stout, much flattened, and very rapidly widening outwardly in both sexes, in the 
male reaching far beyond the middle of the elytra, in the female shorter, joints 3 and 4 subequal, 8-10 
exceedingly large and broad, equal in length, and each much widened towards their apex, 11 very much 
longer than 10; prothorax fully as long as broad, very convex, the sides a little narrowed and sinuate 
behind and feebly rounded in front, the hind angles rather sharp, the base slightly rounded, the basal 
fovere obsolete, the surface very densely and rugosely punctured; scutellum with a few scattered punc- 
tures, rather shining ; elytra rather long, parallel in their basal half, very much broader than the prothorax, 
rather convex but flattened on the disc, with rows of moderately fine, very deep punctures, which beyond 
the middle rapidly become very much finer and shallower, the interstices perfectly flat, very minutely 
punctured, and each with a row of very widely separated coarser punctures, the latter each bearing a long, 
erect hair; beneath a little more shining, dark bronze, finely and rather sparsely punctured, the last 
ventral segment more closely so; legs dark bronze, with a slight violaceous tinge, long, the femora clavate 
in their outer half. 
Length 8-9 millim.; breadth 23-3 millim. (dQ .) 
Hab. Panama, Bugaba 1000 feet (Champion). 
Five examples. ‘This elegant insect is allied to one er two undescribed species from 
the Amazons. 
