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XVII. On the Corpuscles of the Blood. — Part III. By Martin Barry, M.D., 
F.R.SS. L. and E. 
Received June 17, — Read June 17, 1841. 
NOTWITHSTANDING the great length of time during which the blood has been 
the subject of physiological research, an eminent anatomist, so late as the year 1838, 
remarks, that “ we have no clear conception of the mode in which the floating cor- 
puscles of the blood conduce to nourishment'^-.” That Professor Weber was not 
mistaken in coming to such a conclusion, I think will be admitted by every one who 
takes the pains to consult the records of discovery in this most interesting field of 
observation. 
I am not aware that, since the period just mentioned, any additional facts have 
been published, relating to “ the mode in which the floating corpuscles of the blood 
conduce to nourishment,” unless my own communications, already presented to the 
Society^, are to be so regarded, — those communications having reference to the mode 
of propagation of the floating blood-corpuscle, and to its conversion into two or three 
kinds of tissues. 
The object of the present memoir is to bring together a large number of observa- 
tions, made by myself, showing that every structure I have examined arises out of 
corpuscles having the same appearance as corpuscles of the blood. I may here 
mention, that the tissues submitted to actual observation, with the result just men- 
tioned, will be found to include the cellular, nervous, and muscular ; besides carti- 
lage, the coats of blood-vessels, several membranes, the tables, cells, and cylinders of 
the epithelium, the pigmentum nigrum, the ciliary processes, the crystalline lens itself, 
and even the spermatozoon and the ovum. And among the vast number of observa- 
tions made, I have not been able, with the greatest care, to detect a single fact 
inconsistent with the conclusion above announced. If that conclusion — which 
regards the formation of the tissues— be correct, it may, I think, assist us in consi- 
dering “ the mode in which the floating corpuscles of the blood conduce to nourish- 
ment” during life. 
For the detail of these observations, I shall rely principally upon the drawings, and 
the minute explanation of them separately given. The perusal of that explanation 
will, I conceive, be necessary for the understanding of some general remarks I shall 
t E. FI. Weber, in Muller’s Archiv, 1838, p. 463. 
+ On the Corpuscles of the Blood. Philosophical Transactions, 1840, Part II. p. 595 : and Part II. on the 
same subject, in the present volume, p. 201. 
