Dept.] 
NATURAL SCIENCES OP PHILADELPHIA. 
15 
Dr. CoKSE exhibited a specimen of morbid growth of hair upon the cornea 
of an ox. 
Dr. Leidy mentioned, in explanation of this monstrosity, that the hairs in 
the specimen were the result of the excessive development of very minute 
hairs naturally existing at the inner canthus of the eye, in connection with the 
caruncula lachrymalis, and corresponding with the nictitating membrane. 
Dr. Hammond stated that he had been requested by the " Verein fur gemein- 
schaftliche Arbeiten^^ to present to the Department the new forms of '■^Krankheits 
TahelW'' issued by the Verein, and to desire some action of the Department 
thereupon. A Committee was appointed upon the subject, consisting of Drs. 
Hammond, Woodward and H. Hartshorne. 
On the Secondary Formation of Blood Crystals. 
BY WILLIAM A. HAMMOND, M. D. 
Assistant Surgeon, United States Army. 
A few days ago, whilst viewing a slide on which I had four years since mounted 
some blood-discs of a common prairie snake, {Eutaiiiia elcgans) I was surprised to 
find scattered amongst their corpuscles a number of well marked acicular crj's- 
tals, most of them connected in groups, and radiating from a centre as shown 
in the drawing. 
I had not inspected this slide for about five months, and at that time I aiu 
confident the crystals were not present. I had constantly before been in the 
habit of looking at these corpuscles, but had never previously perceived cry- 
stals. 
This is the second time it has occurred to me to discover crystals on slides 
containing blood-discs which must have been formed at a considerable period 
after the preparation of the specimen. The first instance was on a slide on 
which were mounted blood-corpuscles of the soft-shell turtle, [Trionyx ferox). 
Crystals were found on this, some months after it was prepared. On a previous 
occasion, I mentioned this circumstance to the Department. 
The discs in both cases were mounted dry, and covered with paper in the 
1858.] 
