BEALE ON THE NUCLEUS. 59 



the bioplast, or representative of the only living 

 matter, or cy to blast, of the part. This is the case 

 with the continuous tissues, the epithelial cells of both 

 kinds, the fat and starch cells, the capillary walls, the 

 bone cells ; in new growths, and in young and quickly- 

 growing parts, &c. There remains, then, only the 

 so-called nuclei and nucleoli, which exist within the 

 protoplasm, to which the term ought properly to be 

 applied. Dr. Beale dissents from the theory that these 

 bodies are the parts first formed, and which cause the 

 rest to be deposited round them ; and also that they 

 are the sole agents concerned in reproduction. On the 

 contrary the protoplasm is formed first, and these 

 appear in it afterwards. Often subdivision of the 

 protoplasm takes place, and nuclei appear in a portion 

 after it has been detached. They have the same 

 composition as the protoplasm, and are merely new 

 centres of more intense vital activity. " Bioplasm in 

 a comparatively quiescent state is not unfrequently 



worm, informs rue that the cyst from which the pseudo-naviculae 

 emerge remains finely granular, and never breaks up into pseudo- 

 naviculae until the nucleus has opened, and its contents are distributed 

 throughout the sac. The same observer has shown that in the amoeba 

 the nuclei differ sexually, which has been recently confirmed by Grreef j 

 and that the transfusion of their contents is needful for multiplication 

 by this method (" Proc. Lit. and Phil. Soc., Liverpool," 1871 2, pp. 

 297, 8). In the vorticella, besides the methods of increase by fission 

 and gemmation, there is also a true sexual mode of multiplication, in 

 which the vorticella encysts, the cilia and pedicle disappearing, and the 

 nucleus, which with very high magnification is shown to have an 

 enclosed nucleolus, rupturing soon leads to the breaking up of the 

 forms into a number of sub -spheroidal germs, which are set free by the 

 breaking up of the cyst ; and after some little time of locomotive life, 

 these develop into fresh vorticellae. 



Many other examples might be given, but these will suffice to show 

 that in independent organisms, the nucleus and nucleolus may be, 

 in fact, organs whose use is known, or as yet unknown, and not essential 

 components of living matter in the abstract. 



