58 BEALE'S PROTOPLASMIC THEORY. 



a cell wall, within which the latter accumulates. This 

 applies to the flask-like cells, the fat cells, and the 

 starch cells, c., and also to the more complicated 

 ciliated cells. There is no difficulty of seeing how 

 this applies to continuous tissues, and all matters 

 enumerated as dead at p. 45 ; and there is no neces- 

 sity of straining the theory to make it fit, as was the 

 case with the old cell theory, where nothing like the 

 transformation of a typical cell could be seen in most 

 cases. But the question of the nucleus is more diffi- 

 cult ; and here the definite conception of Beale brings 

 order and clearness out of the confusion and obscurity 

 which prevailed. In the first place a number of objects 

 are simply falsely called nuclei, and are nothing but 

 oil-globules, &c., resulting from post-mortem changes 

 in germinal matter ; or are granular and other foreign 

 bodies. Next, in many independent organisms of low 

 order, such as algaa, monads, and infusoria, the so- 

 called nucleus is really an organ, though its use is not 

 yet determined."' Again, the term nucleus is really 



* That the nucleus is not an essential element, but a special organ, 

 performing, when present or visible, some more or less manifest part in 

 the process of reproduction, becomes more and more apparent as the 

 lower forms of life are more efficiently studied. It is now well known 

 that in Taramccia the reproduction is partly by fission and partly 

 sexual. The sexual mode, when carefully studied with sufficient power, 

 leaves no doubt as to the fact that both the nucleus and the nucleolus 

 are special organs the nucleus being the ovary, and the nucleolus the 

 testis ; for it is only after the mingling of the elements contained 

 respectively in these that any sexual multiplication takes place. Van 

 Beneden has studied the development of Gregarinse from pseudo-filaria, 

 which are at first simple threads of protoplasm. After a short period 

 of quiescence a nucleolus forms but by what means this is distin- 

 guished from the nucleus is not stated ; but it takes its rise in elements 

 previously contained in the protoplasm. Then the nucleus is formed ; 

 but its function is said to be unknown. But the Rev. W. H. Dai- 

 linger, who has given careful study to the Gregarinse from the earth- 



