37 2 -ft'jnv York State Agricultural Society. 
mater, a mite was seen running upon the corpus callosum near the 
pineal glaud. He also states that M. Lauth, professor of anatomy, 
showed him a little insect he had found near the base of the brain, on 
the surface of the pituitary gland, in a deceased maniac in the hospi¬ 
tal, which everybody took to be a crab-louse, but which Hermann 
knew to be a species of mite closely resembling in size and color the 
Acarus cellar is, which he frequently met with in the moist earth in a 
corner of his cellar. 
There can be little doubt that in many cases these mites are pre¬ 
sent in one part and another of the body, and that under certain 
circumstances they occasion lesions and diseases, of which the most 
competent members of the medical profession are unable to conjecture 
the cause. I here present an interesting instance of this kind: 
A young lady applied to Z. Cotton, dentist, now some years located 
at Cambridge, N. Y., to extract a tooth from which she was suffering 
much pain. He found the tooth complained of to be perfectly sound 
and all its surroundings healthy; he therefore felt averse to removing 
it, and proposed a resort to soothing, external applications, whereby 
the pain perhaps would after a time pass away. It, however, was 
occasioning her so much torment, no external applications having 
given the slightest relief, that she insisted upon having it taken out. He 
accordingly extracted it. On then inspecting it, he could perceive no 
traces of caries, ulceration, or other disease which should cause it to 
have been painful. While thus looking attentively at the tooth, he 
noticed, by its moving, that there was a minute insect upon the side 
of the tooth, partly between its roots. This was a discovery indeed. 
From the place where it was located when it was first seen, Mr. C. 
is confident it was not situated between the fleshy gum and the tooth, 
nor could it, in extracting the tooth, have been rubbed from off the 
gum to be at the point where it was. Evidently it was situated a 
short distance within the alveolus, insinuated into the suture between 
the tooth and the wall of its bony cavity. And he thinks, with rea¬ 
son, it was this mite that had caused the pain which the patient had 
experienced in this tooth. 
He inclosed the specimen in a small vial and presented it to me. 
As the dysentery-mite, Sarcoptes Dysenterice, occurs in the mouth as 
well as in the stomach and intestines, I suspected this would perhaps 
be that insect, or a species very similar to it. But it proves to be 
quite different. It is so minute, and the specimen is so contracted in 
drying, that I am unable to draw from it a description that is com¬ 
plete and perfect. The characters which follow, however, are ample 
