309 
and more protuberant in P. gopheri and are placed lower down on the 
sides of the head, so that they can be seen from beneath; in both the 
related species the eyes are flat. more elongate and are not visible from 
beneath. 
From P. discoideus it is readily distinguished by the long antennie 
and the sexual characters of the male. <As is the ease with Aphodius 
troglodytes this insect turns darker after death. In life its color is pale 
yellow like the sand in which it lives. 
Chelyoxenus n. g. 
Head retracted; antennze inserted under margin of the front; prosternum not 
lobed anteriorly, convex, bistriate; antennal fossze immediately in front of the an- 
terior coxe; mesosternum truncate anteriorly; elytra with five dorsal strie, the 
four outer ones nearly entire, the fifth abbreviated and usually appendiculated at 
apex; pygidium triangular, convex, greatly and rather suddenly inflexed apically; 
femora not incrassated; front tibice dilated and multi-dentate; middle and hind 
tibize slender, biseriately spinose; tarsi of middle and hind legs slender; claws 
strikingly unequal in length: the inner one very slender and almost as long as the 
claw joint, the outer one spine-like and only about one-fourth the length of the 
inner claw. 
This new genus of Histeridie is proposed for a rather small species 
which agrees with Saprinus in all essential characters excepting the 
structure of the tarsal claws. Uni-unguiculated genera of Histeridze 
are known both in the Histrini (Cypturus and Monoplius) and Saprini 
(Xiphonotus), but Lam not aware that a genus has been described 
exhibiting a marked inequality of the claws. Superficially, this genus 
may be distinguished from Saprinus by the more complete elytral stria- 
tion and also by the somewhat less ovate and less convex form of the 
body. 
Chelyoxenus xerobatis n. sp. 
Oval, shining, black, without metallic retlectious. Head sparsely, minutely 
puuctulate, front not margined, supra-orbital stria distinct, extending a short 
distance upon the front. Thorax fully twice as wide as long, sides con~er- 
gent anteriorly and nearly straight from the base to apical fourth, thence arched; 
a single marginal stria; very finely and sparsely 
punctulate on the disk, more coarsely and densely ~ 
on the sides. Elytra at apex finely, sparsely and 
rather irregularly punctate, the punctures extend- 
ing slightly between the striw, the remainder of the 
elytral surface very minutely and sparsely punctu- 
late; a single very long subhumeral stria usually 
but slightly abbreviated at either extremity, some- 
times interrupted or obsolete anteriorly; oblique 
humeral stria long, distinctly impressed; dorsal 
striae 1 to 4 subequal in length, extending from the 
base nearly to the apex of the elytra, deeply im- 
pressed and obsoletely punctured, not hooked at  F'G-19.—Chelyoxenus xerobatis: a, b, 
base, fourth arched at base, joining the sutural stria, eeahiis mu clyssal Gola iee, 
é ’ E f e, claw of left hind leg—enlarged 
which is strongly impressed and entire; between the (original). 
fourth dorsal and the sutural a strongly impressed 
fifth stria of varying length, beginning sharply a short distance below the arch, fre- 
quently interrupted and continued by punctures at the apical end, where it is accom- 
