n
several species.

[Illustration: 144. Cheyletus.]

These insects often suddenly appear in vast numbers on various articles
of food and about houses, so as to be very annoying. Mr. J. J. H.
Gregory, of Marblehead, Mass., has found a mite allied to the European
species here figured (Fig. 144) very injurious to the seeds of the
cabbage, which it sucked dry. This is an interesting form, and we have
called it Cheyletus seminivorus It is of medium size, and especially
noticeable from the tripartite palpi, which are divided into an outer,
long, curved, claw-like lobe, with two rounded teeth at the base, and
two inner, slender lobes pectinated on the inner side, the third
innermost lobe being minute. The beak terminates in a sharp blade-like
point.

We have received a Cheyletus-like mite, said to have been "extracted
from the human face" in New Orleans. The body is oblong, square behind;
the head is long and pointed, while the maxillae end in a long, curved,
toothed, sickle-like blade. That this creature has the habits of the
itch mite is suggested by the curious, large, hair-like spines with
which the body and legs are sparsely armed, some being nearly half as
long as the body. These hairs are covered with very fine spinules. Those
on the end of the body are regularly spoon-shaped. These strange hairs,
which are thickest on the legs, probably assisted the mite in anchoring
itself in the skin of its host. We have read no account of this strange
and interesting form. It is allied to the Acaropsis Mericourti which
lives in the human face.

A species, "apparently of the genus Gamasus," according to Dr. Leidy,
has been found living in the ear (at the bottom of the external auditory
meatus, and attached to the membrana tympani) of steers. "Whether this
mite is a true parasite of the ear of the living ox, or whether it
obtained access to the position in which it was found after the death of
the ox in the slaughter house, has not yet been determined."

We will now give a hasty glance at the different groups of mites,
pausing to note those most interesting from their habits or relation to
man.

The most highly organized mite (and by its structure most closely allied
to the spider) is the little red garden mite, belonging to the genus
Trombidium, to which the genus Tetranychus is also nearly related. Our
own species of the former genus have not been "worked up," or in other
words identified and described, so that whether the E