OF WASHINGTON. 161 
8. Xenistusa fossa ta, 
9. " pressa. 
The three last-named species have hitherto been found only at Columbus, 
Tex. They occurred in a prostrate, but not decayed, trunk of Celtis texana, 
which was honeycombed by a large colony of Termes. Specimens were 
quite abundant in the galleries of the white ants, but since the wood was 
very hard they had to be cut out with an axe and on account of this awk- 
ward mode of investigation only a few could be secured. When alive, and 
when examined shortly after being killed, they seemed to represent three 
species ; they were sent so to Dr. Leconte and accordingly described by 
him as three different species. However, from the descriptions and the 
dried specimens in our collections, it is difficult to distinguish the species, 
and quite impossible to conceive a correct idea of the peculiar appearance 
of these insects when alive. With their cylindrical body, their greatly ex- 
tended abdomen, and their peculiar mode of locomotion, they resemble 
much more the wingless white ants than we would suspect from the dried 
specimens. They are by far the most remarkable termitophilous Coleop- 
tera hitherto discovered in North America. If they should be found again 
they ought to be put in weak alcohol so as to preserve their original shape 
and to enable a more careful description of their structural characters, and 
more especially the secondary sexual characters on the last ventral segment. 
Next to this genus in resemblance to their hosts are the species of Philo- 
tcrmes. This is the only genus which, in my experience, wanders about 
with the White ants in their subterraneous foraging expeditions, and 
which may be found among them in early spring under stones, old bark, 
etc. But the specimens are more abundant in the nests of the white ants, 
and the other genera are only found within the true nests of their hosts, 
or verv rarely in their immediate vicinity. The genera Myrmecochara, 
Microcyptits, and Trichofiscnius have little or no resemblance to Termes, 
but they all have that peculiar appearance at once suggestive of an inquili- 
nous or parasitic mode of life such as we are accustomed to see in most 
myrmecophilous and parasitic Coleoptera. The general similarity in ap- 
pearance and superficial structural characters between Microcyptus and 
Limulodes, a myrmecophilous genus of the family Trichopterygidce, have 
already been pointed out by Dr. Horn (Trans. Am. Ent. Soc., vi, 1877, p. 
87), and no one can deny a certain superficial resemblance, though not in 
any structural details, between Trichopsenius and the beaver parasite, 
Platypsyllus castoris. 
All species in the above list were found among Termes flavipes, and it 
will be noticed that, except in the Southern States, they have hitherto been 
observed only east of the Alleghanies. 
Specimens of the species mentioned were shown by Mr. 
Schwarz. 
Some discussion on the place of these insects in the economy 
of Termes took place between Mr. Schwarz and Prof. Riley. 
