43 Mr. H. J. Carter on Amoeba princeps 



(fig. 1 c, d), which I have described ? and could the latter have 

 been some of these cells which had passed into young Amceba 

 in the body of the parent ? 



Granulation of the Nucleus (PI. III. fig. 2). — We come now to 

 what is probably a granular propagative change taking place in 

 the nucleus, without subdivision into the reproductive cells just 

 described. 



This change commences a little before the Amoeba has arrived 

 at half the adult size, and when the nucleus is about , ^\ ^ th 

 of an inch in diameter. After this, the nucleus increases in 

 bulk, as the granulation which is taking place in the nucleolus 

 becomes more and more coarse and evident, until, towards the 

 adult size above mentioned, it obtains an oval and apparently 

 flattened form, about -rfo^h of an inch long (fig. 2/). The 

 capsule or nuclear cell has now become much thicker, and 

 the granules of the nucleolus, which ^e spherical bodies com- 

 posed of yellowish, semiopake, refractive matter, about , ^ ooo ^b^ 

 of an inch in diameter ; but the Amoeba at this period is as 

 active as in any former part of its existence. 



Of the ultimate development here also I am ignorant, but 

 presume that here too the parent membranes become eiSPete, 

 and that the nucleus, bursting, gives freedom to the granules of 

 the nucleolus, in the form of so many polymorphic ciliated cells, 

 which, as in other similar cases, lose their cilia, and finally become 

 reptant young Amoebce. 



Spermatozoids. — Lastly we come to this element ; and although 

 the act of generation, where there is a combination of the proto- 

 plasm of different cells, seems only to be the dividing up of the 

 contents of one cell into smaller portions than that of the other, 

 that the former may be added to the latter after the manner that 

 increments of matter are added to a balance to make up a certain 

 weight or quantity, still it is necessary for us not only to have 

 this unequal division of the protoplasm into separate living or- 

 ganisms, but to see that they bear certain signs which distinguish 

 the ovum and the spermatozoid, and then, if possible, that the 

 two combine, before we be satisfied that such elements are for 

 propagation by this process. 



Now, as yet I have never seen (to my knowledge) either one 

 or the other in A. princeps. I could perceive no germinal vesicle 

 nor anything like a nucleus in the cells formed by the division 

 of the nucleus ; and I do not know what the form or course of 

 the granules of the granulated nucleus may be in their ultimate 

 development, or of the granuliferous cells which are seen among 

 the reproductive ones (fig. 1 d). But I did see bodies for which 

 I am not able to account, viz. : — 



1st, Several granuliferous cells which were with the repro- 



