SPLENIC DISEASE. 
321 
than is found in their histological structure; and even this is 
slight, consisting merely in both possessing canals containing 
vessels, and surrounded by concentric zones formed of very 
dissimilar materials. Here the resemblance ceases ; there 
are no lacunae or canaliculi in the horn, nor cellular or 
fibrous arrangements in the bone, and the chemical composi- 
tion of both are notably different. 
From its situation, its structure, its composition, and its 
analogies, then, we are justified, I think, in concluding that 
the horse’s hoof is identical with the cuticle or epidermis, the 
modifications observed in it being destined to meet the altered 
requirements of the covering at the extremity of the limb. 
The horny carapace of the horse’s foot is peculiar, therefore — 
though this peculiarity extends to all the hoofed quadrupeds — 
in being fibrous, a character it owes to the disposition of the 
minute epithelial cells of which it is composed, these being so 
arranged that when condensed by the animal’s weight and 
other influences, they constitute visible fibres, which are 
generally perpendicular to the plane by which the super- 
incumbent pressure is transferred to the ground. 
In order to perfectly understand this interesting disposition 
of cells in the hoof, I have carefully and patiently examined 
it with the aid of the microscope, and have noted the following 
results of this examination. Before referring to them, how- 
ever, I would beg to impress upon the members of the 
veterinary profession the great importance of familiarising 
themselves to the use of this wonderful instrument, which so 
marvellously extends the range of vision, intellectually and 
physically. By it and chemical reagents can we alone hope 
to unravel many of the mysteries of vitality, and no 
anatomist, physiologist, or pathologist deserves the designation 
who is unacquainted with its employment, or the discoveries 
to which its introduction into these branches of science are 
mainly due. 
SPLENIC DISEASE. 
By John Gerrard, M.B.C.V.S., Market Deeping. 
With the great and increasing demand for animal food has 
arisen the question how best to secure it. It will be found, 
on inquiry, that this demand, by leading owners of stock to 
hasten the processes of nature, inducing thereby precocious de- 
velopment, has in no small degree contributed to the production 
