275 
of the Ama^^on Valley. 
Genus AposPHiERioN, nov. gen. 
Thorax elongatus^ angustatus, cylindricus, omnino 
Isevis. Antennae articulis 3-11 sulcatis^ carinatis, et 
(llmo excepto) apice spinosis. Pedes breves ; femora 
abrupte clavata^ inermia. 
Differs from all the other genera of Sphceriince in the 
form of the thorax^ which is greatly elongate^ and 
almost perfectly cylindrical, without a trace of lateral 
spine or dorsal inaequalities or punctures ; it has only a 
single transverse curved impression near the base. The 
elytra are nearly twice the width of the therax at the 
base, and taper regularly thence to the apex, where they 
are truncate and bispinose, the sutural spine much the 
smaller ; the surface is nearly impunctate, except at the 
base, where, for a small space, they are very strongly 
punctured, and there are only a few long hairs. The 
chief peculiarity of the genus, however, is in the an- 
tennae, without which I should have hesitated to se- 
parate it from Periboeum. This consists in the grooves 
and carinae, which in the allied genera are confined to 
the third, fifth, or sixth joints, but are here extended to 
the apex ; all these joints being spinose at the tips, ex- 
cept, of course, the eleventh. The legs are short, and 
the femora abruptly clavate, and quite unarmed at the 
tips. The palpi are extremely short, with the terminal 
joints triangular. The intermediate sockets are closed ; 
the anterior haunches are globular, with the narrow pro- 
sternum sunk between them. 
Notwithstanding the cylindrical form of the thorax, 
the genus has not at all the facies of Ihidion, a circum- 
stance which arises from the thorax not having the 
arched appearance characteristic of the Ihidion group. 
1. Aposphcerion longicolle, n. sp. 
Angustatum, castaneum, politum ; capite antice spars© 
punctato ; thorace cylindrico, laevi, prope marginem pos- 
ticum arcuatim sulcato ; elytris postice attenuatis, apice 
bispinosis, supra laevibus, prope basin aspere punctatis, 
postice prope suturam punctis nonnullis setiferis. 
Long. 4^-71 lin. ^ $ . 
Hah. — Obydos, Lower Amazons ; on branches of dead 
trees. 
