180 
MR. TOYNBEE ON THE ORGANIZATION AND NUTRITION 
Of the Vessels which nourish the Cornea. 
Previous to giving the results of my researches upon the manner in which the 
cornea is supplied with a nutrient fluid, I shall detail the following opinions of au- 
thors upon its vascularity. 
M. Boyer. “ La cornee regoit des vaisseaux sanguins, puisqu’elle devient rouge 
dans les fortes inflammations ; mais ces vaisseaux sont si fins, que finjection ne peut 
y ptmetrer, et que la partie rouge du sang ne s’y introduit qu’en quelques circon- 
stances. On n’a point encore decouvert de nerfs dans cette membrane*.” 
M. Cruveilhier. “ Les injections les plus fines, passees dans les veines et dans 
les arthres de 1’oeil, ne demontrent aucun vaisseau dans la cornee-f.” 
Mr. Jacob. “ The cornea is destitute of red vessels, yet it affords a signal example 
of a colourless and transparent texture possessing vital powers inferior to no other^;.” 
Mr. Lawrence. “The cornea in its natural structure consists of cartilaginous 
laminae and mucous membrane ; the cornea is analogous to the articular ends of the 
bones, in which the articular cartilage is covered by synovial membrane. It (the 
cornea) agrees with them, (the fibrous structures) in the entire absence of vessels cir- 
culating coloured fluids ; perfect transparency being essential to its office of transmit- 
ting light §.” 
M. Muller. “The existence of vessels in the substance of the cornea is doubtful; 
they have never been injected. Nevertheless, penetrating ulcers and granulations are 
formed in the cornea, which can scarcely be conceived to occur without the agency 
of vessels. I have repeatedly seen in Calves of nearly the full time, vessels in the 
conjunctiva of the cornea, which contained red blood, and which could with a lens be 
traced more than a line over the margin of the cornea. Henle has injected these 
vessels ; in the conjunctiva of the cornea they measured x sY ath to yyyth of an inch, 
and the finest twigs were not then injected ; their trunks, which arose from a circular 
vessel that ran around the cornea, were even somewhat larger than this. The pre- 
parations of these parts I have in my possession. Professor Retzius has, by means 
of injection, been able to see the same thing in the adult animal. 
“ All these facts, however, render it very probable, that even the cornea and capsule 
of the lens, to which vasa serosa have been hitherto ascribed, are really provided with 
vessels carrying red blood. The vessels of the corneal conjunctiva are certainly less 
numerous than those of the sclerotic conjunctiva; there is the same difference between 
these two parts as between that part of the synovial membrane which is free, and that 
which covers the articular cartilage ||.” 
M. Romer. “ Romer of Vienna has described the arteries which ramify from the 
* Traite d’Anatomie, quatrieme edition, 1815, vol. iv. p. 98. 
f Anatomie Descriptive, 1815, vol. iii. p. 462. 
\ Cyclopaedia of Anatomy, vol. ii. p. 177. 
§ On the Diseases of the Eye, 1833, pp. 16, 368. 
|| Muller’s Elements of Physiology by Baly, vol. i. pp. 215, 216. 
