THE PsELAPHIDAZ OF NorTH AMERICA. 81 
the third, fusiform, five times longer than wide, acuminate. 
Antenne, excluding the last joint, as long as the head and pro- 
thorax, first to eighth joints obconical, regularly decreasing in 
size; ninth and tenth respectively as wide as the second and 
first, sub-globose, nearly transverse; eleventh one-half thicker 
than the tenth, more convex outside, as long as the three pre- 
ceding. Prothorax widest across the anterior fourth, anterior 
circumference semi-circular, sides straight from the anterior 
third to the basal angle, rounded, not margined; disk evenly 
vaulted, with a large, deep, median fovea, lateral fovez small 
and shallow; on each side of the large fovea is an inconspicu- 
ous tubercle, and there are two shallow impressions on each 
side near the base; median basal carina present, median, 
transverse, and lateral sulci wanting. /ytra rather convex, 
with obsolete shoulders, as in some Californian Aatrzsz, the 
sutural lines close together, discal lines wanting; there are two 
shallow impressions near the base. Addomen wider than the 
elytra, nearly as long as the prothorax and elytra, without a 
visible line of junction between the dorsals and ventrals above, 
not margined; basal dorsal segment three times wider than 
long, basal foveze deep, the median twice as wide as the lateral 
ones; second and third segments sub-equal, together as long 
as the first; fourth half as long as the abdomen; fifth very 
short, emarginate at the tip. Prosternum short, the coxal 
cavities continuous, coxe large, conical; mesosternum cari- 
nate, narrow anteriorly, bilobed, the posterior coxe separated 
by a distance equal to the length of the last palpal joint. 
Legs, coxe, and trochanters simple, not spinous, femora 
strongly clavate, tibia moderately arcuate, the posterior ones 
with a very small terminal spinule inside; tarsi half as long as 
the tibize, first joint short, second longest, more than half the 
length of the tarsus, thicker at the distal end, third, cylindrical, 
thin, with but one perceptible claw. To all appearance the 
unique specimen described is a male; the ventral segments 
correspond to the dorsals in length, the fourth segment bears 
a large, deep, transverse fovea, and the fifth is semi-circular. 
