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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. 



feOME time since, I laid before the Royal Society a few facts, which had incident 

 tally fallen under my notice, connected with the red particles or corpuscles of the 

 blood -J~. 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 efi'ected 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 niay 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 diflferences 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, 



t Philosophical Transactions, 1840, Part II. p. 595. 



