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XVI. On the Corpuscles of the Blood. — Part II. By Martin Barry, M.D., F.R.SS. 
L. and E. 
Received January 13, — Read January 14, 1841. 
SOME time since, I laid before the Royal Society a few facts, which had inciden- 
tally fallen under my notice, connected with the red particles or corpuscles of the 
blood-f-. Those facts were of a character which led me to expect that the farther 
prosecution of the subject might be rewarded by the discovery of others; although, 
in a field of physiological research so often traversed from the days of Malpighi and 
Leeuwenhoek down to the present time, I could hardly expect to succeed in making 
any addition to the exact description given by some able writers of the present day, 
regarding the appearance of these corpuscles. But some ideas suggested during the 
examination of objects figured in the memoir just referred to, induced me to make 
the blood-corpuscles the subject of direct inquiry with reference to their mode of 
origin, and certain changes which they undergo. 
It will be remarkable if the mammiferous ovum, which, because of its minuteness 
and the supposed difficulty of obtaining it, had been generally considered beyond 
the reach of satisfactory observation, should now become the means of studying', not 
merely other ova, but certain processes by which nourishment is communicated, and 
the growth of the body effected at all future periods of life. Such, however, I think 
will really be the case. 
For the sake of avoiding a great deal of repetition, I shall at present confine my- 
self very much to the general results ; referring, for a particular description of the 
figures which accompany this memoir, to the minute explanation of them separately 
given (par. 87.). I may here state that, instead of perplexing the reader with mea- 
surements expressed in arithmetical figures, I have thought it preferable in all the 
drawings to represent the lines of the micrometer on which the objects lay ; which 
lines are more particularly referred to at the foot of Plate XVII. I have taken the 
utmost care to represent faithfully the appearances presented by the objects exa- 
mined ; and an inspection of them will show that the undertaking occupied no small 
portion of time. Some of the differences between the drawings now presented and 
those of previous observers, are, I think, to be attributed to my having used a greater 
degree of care in the removal, by the usual means, of a portion of the colouring 
matter from the corpuscle, where required (par. 72.). In other instances, however, 
f Philosophical Transactions, 1840, Part II. p. 595. 
