464 ANATOMY AND PHYSIOLOGY OF THE HORSE’S FOOT. 
and crustaceous animals. The skin of these creatures, as is 
well known, is more or less horny in its texture, and is further 
strengthened or consolidated by the peculiar animal substance 
named chitine. The desiccated lamina, in colour and con- 
sistence, is not unlike this epidermic carapace of beetles; 
and the horizontally stratified arrangement of its fusiform 
cells, always running in the same direction, adds to this re- 
semblance. This chitinisation of the epidermic cells of the 
Coleoptera and other creatures, we must remember, not only 
confers strength and rigidity on the thin epidermis, but also 
endows it with a great amount of elasticity; indeed, some 
histologists, and among them Leydig, have not hesitated to 
assert that the chitinised conjunctival tissue of the inverte- 
brata should be placed on the same footing with the elastic 
tissue of vertebrata. 
In describing the horny and vascular laminse, when speak- 
ing of the anatomy of the foot, I referred to the existence of 
lateral laminellse or lamellae on these, and mentioned that I 
first observed them in 1858 * The presence of these beautiful 
appendages is easily verified by making a thin transverse 
section of the horny and vascular laminae from any part of 
the front of the foot. I usually prepare the foot, in order 
more readily to obtain good sections, by steeping it, when in 
the fresh state, in a moderately strong solution of carbolic 
acid, and afterwards thoroughly drying it. In making the 
section the ends of the horny laminae generally become a 
little distorted, while the extremities of the vascular leaves 
at the base of the horny ones often tear in places. Such has 
been the case in Plate II. 
With a low magnifying power they appear as in this 
* Mr. Armatage, M.R.C.V.S., lias informed me, since the above was 
written, that the late Professor Barlow, of the Edinburgh Veterinary 
School, mentioned and showed these lamellae to his private histological class 
so early as 185 1 . I was not previously aware of this, probably in conse- 
quence of my not having attended the special class while at the Edinburgh 
School a short period after this date. They were also alluded to in a paper 
on the “ Structure of the Horse’s Hoof” (“ Osservazioni .... intorno all’ 
organo Keratogene”) by Professor Ercolani, of Turin, in the veterinary journal 
of that city, in 1861. About the same period they were also noticed by 
Professor Rawitz, of St. Petersburg, who published a paper on the subject 
in the Magazin de Gurlt. Professor Gourdon makes no allusion to them in 
his series of papers on the “ Corne du Sabot du Cheval,” published in the 
Journal du Midi, for 1865; indeed, they do not appear to have been 
observed in France until Professor Colin, of Alfort, indicated their existence 
in a communication to the Central Veterinary Society of Paris in 1867 
(Recueil de Med. Veterinaire ). The late Dr. Hepworth, of Croftsbank, Man- 
chester, to whom, several years previously, I had given my 1858 preparation 
showing these lamellse, published a description of them in the Micro- 
scopical Journal for 1865, designating them as the <c laminellse of Fleming.” 
