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XIII. Researches , tending to prove the Non-vascularity and the peculiar uniform Mode 
of Organization and Nutrition of certain Animal Tissues, viz. Articular Cartilage, 
and the Cartilage of the different Classes of Fibro-Cartilage ; the Cornea , the 
Crystalline Lens, and the Vitreous Humour ; and the Epidermoid Appendages. 
By Joseph Toynbee, Esq., Member of the Royal College of Surgeons, London, and 
late Assistant to the Conservators of the Museum of that Institution. Communi- 
cated by Sir Benjamin C. Brodie, Bart. F.R.S. 8$c. &;c. 
Received April 21, — Read May 20, 1841. 
Introduction. 
It is now generally acknowledged that the process of nutrition in most animal 
tissues consists in changes undergone by the nutrient liquor sanguinis, which has 
exuded into them through the coats of the capillaries ramifying throughout them. The 
vessels themselves vary in number in different structures : in muscle, the capillaries 
are very numerous, and the spaces between them very small ; whilst in tendon and 
ligament, on the other hand, the latter are comparatively large ; but in all structures, 
whatever may be the degree of their vascularity, the tissue the furthest removed 
from the vessel is nourished equally well with that which is in immediate contact 
with it. 
In all vascular structures, therefore, there is of necessity a considerable extent of 
tissue which is nourished without being in contact with blood-vessels, and the know- 
ledge of this fact forms a necessary introduction to the study of the process of nutri- 
tion in those organs, into which, whilst in a healthy state, anatomists have never 
succeeded in tracing blood-vessels. The organized tissues, constituting such non- 
vascular organs, may be divided into three classes : 
The first, comprehending articular cartilage, and the cartilage of the different 
classes of fibro-cartilage ; 
The second, the cornea, the crystalline lens, and the vitreous humour ; 
The third, the epidermoid appendages, viz. the epithelium, the epidermis, nails 
and claws, hoofs, hair and bristles, feathers, horn, and teeth. 
It is to these tissues that the investigations I have now to communicate relate : I 
shall endeavour to prove that no vessel ever enters them when they are perfectly 
developed, and in a healthy state, and to demonstrate the manner in which they are 
nourished. 
In the first place, no anatomist has ever been able to trace vessels into these tissues 
