Spermatozoa into the Interior of the Ovum. 327 



For it will be found stated in that communication : " These 

 ova were submitted to the inspection of Professor Owen, and 

 I afterwards shewed one of them to Professors Sharpey and 

 Grainger, all of whom agreed that the spermatozoa were 

 contained within the ovum" Dr Nelson will also find it re- 

 corded in a note added to that communication in the Philo- 

 sophical Transactions for 1843, while it was passing through 

 the press, that I had seen the same thing a second time ; 

 having met with several ova containing spermatozoa in their 

 interior in another rabbit. An account of this second obser- 

 vation he will also find in the Lancet of April 8, 1843, p. 53. 

 And the Edinburgh New Philosophical Journal for October 

 1843, contains a drawing (Plate V., fig. 1.) in which seven 

 spermatozoa are represented in the interior of an ovum, be- 

 sides the statement (p. 212), that in one instance I had counted 

 more than twenty spermatozoa in a single ovum.* 



Dr Nelson therefore was mistaken in supposing " the fact 

 of the penetration of spermatozoa into the ovum" to have 

 been first " distinctly seen and clearly established" by his 

 own observations. He merely added a further confirmation 

 in ova of an Entozoon, to what my researches on mammife- 

 rous ova had enabled me to record as an established fact 

 nine years before. 



Researches in Embryology : a Note supplementary to Papers 

 published in the Philosophical Transactions for 1838, 

 1839, and 1840, shewing the confirmation of the principal 

 facts there recorded, and pointing out a correspondence 

 between certain Structures connected with the Mammife- 

 rous Ovum and other Ova. By Martin Barrf, M.D., 

 F.R.S., F.R.SJE.t 



Referring to his account of the process of fecundation of 

 the mammalian ovum and the immediately succeeding phe- 

 nomena, published in various papers in the Philosophical 

 Transactions, the author calls attention to the confirmation 



* " On Fissiparous Generation," Edin. New. Phil. Jour., Oct. 1843, p. 212. 

 t From the Proceedings of the Royal Society of London, 16th June 1853. 



