Memoirs on the coleoptera

TENEBRIONID.E 165
small, sparse and obsolescent externally, more distinct and irregular
suturally; abdomen shining, somewhat strongly but finely, confusedly
creased; legs moderately long, slender. width 10. ^ mm. Kansas
Length (9) 22.0
facilis n. sp.
mm. ;
There are many forms in southeastern Arizona allied to obovatus,
and they are rather confusing, but with prolonged study, begetting
more intimate familiarity, the separation of the species and sub-
species finally becomes much less uncertain, and in fact, as they are
now arranged in my cabinet, there would scarcely seem to be any
great amount of error. Nitidipennis and gliscans probably are
species different from obovatus. In one of the specimens
of con-
vexus before me there is a rather notable deformation of the right
antenna, in which the outer joints are much shorter than those of
the left antenna, the tenth joint being a rounded solid mass which
includes the eleventh, the true spongy apex of the tenth being evident
only
in outer half of the width at about the middle.
Heterasida n. gen.
In general facies and many features of its organization this genus
differs very markedly from any of the preceding and is indeed wholly
isolated in the Asidini. The antennae form one exception
in the
tribe in having the entire periphery of the apex of the tenth joint
spongy-pubescent, and the nature or disposition
of the vestiture
is also to a greater or less degree peculiar. The type of elytral
costulation is approached elsewhere only in Asidina, so far as noted.
In the structure of the head and eyes, labrum, prosternum and some
other general characters it does not differ essentially from Euschides
and many other generic groups, but the fourth palpal joint
large and scalene in the male but small and recti-triangular,
is not
as in
all the following genera from this point in the series, and the anterior
tibiae much more nearly resemble those of Pelecyphorns, differing
greatly from Euschides in being more cylindric, with the outer angle
at apex barely at all everted or acute; the tarsi are spinulo-setose
beneath. The mentum is very moderate in size, obtrapezoidal,
mounted upon a high gular pedestal and does not quite attain the
sides of the buccal opening even anteriorly; the acutely pointed sides
of the opening are much prolonged and well developed when com-
pared with some other genera, such as Glyptasida and Pelecyphorus,