Mr. H. W. Bates on the Longicorns of the Amazons Valley. 191 
XXII.— Contributions to an Insect Fauna of the Amazons Valley. 
CoxeorrerA: Lonaicornes. By H. W. Barss, Esq. 
[Continued from p. 42.] 
Subtribe DesMIPHORIT#. 
Group Hwocentrine. 
Genus Exocentrus, Mulsant. 
Mulsant, Coléopt. de France, Longicornes, p. 152. 
Exocentrus is a well-known genus of wide distribution, and 
comprising a number of small Lamiaires, of ovate or oblong form 
of body with thorax armed on each side with a distinct acute spine. 
The antennz are not much longer than the body in the most slen- 
der species, and are generally setose ; the basal joint is of moderate 
length, forming an elongate club thickened almost from the base. 
The claw-joints of the tarsi are elongated but slender, and the 
claws are widely divergent. The genus may be known from all 
the genera of Acanthocinite by thesockets of the anterior thighs 
being open or angulated on their outer edges. 
1. Ezocentrus striatus, n. sp. 
E. oblongus, convexus, fusco-ferrugineus, griseo sparsim pubescens ; 
antennis corpore paulo longioribus, pubescentibus ; oculis magnis, 
supra fere contiguis; thorace pone medium spina valida longa 
armato; elytris striato-punctatis ; pedibus testaceo-ferrugineis, 
femorum clavis fuscis. Long. 37 ln. 
Head rather narrow; sides occupied by the voluminous eyes, 
which also almost meet on the vertex; muzzle below the eyes 
short but rectangular; rusty brown, clothed with hoary pile. 
Antenne filiform, a little longer than the body, clothed with laid 
pubescence, rusty brown, bases of joints reddish ; basal joint of 
nearly equal thickness throughout, eradually narrowed near the 
base. Thorax subquadrate, very little narrowed behind, each 
side, behind the middle, armed with a long, stout, slightly curved 
spine ; surface thickly punctured and sparsely clothed with re- 
cumbent shining hoary pile. Elytra oblong, convex, a little nar- 
rowed towards the apex, the latter rounded ; surface punctured im 
rows, except about the suture near the base, where they are very 
closely punctured ; the scant hoary pile lies in lines along the 
interstices; colour rusty brown. Body beneath rusty brown, 
thinly clothed with shining hoary pile. Legs moderately elon- 
gate, pale reddish ; thighs strongly clavate, clubbed part blackish. 
Santarem, on slender dry twigs. 
2. Exocentrus nitidulus, n. sp. 
E. oblongus, convexus, fusco-ferrugineus, nitidulus, pube sparsa 
