NUCLEI AND NUCLEOLI DO NOT PRODUCE MATERIAL. 55 



of living bioplasm. Within tliem a second series 

 (nucleoli) is sometimes produced. Marvellous powers 

 have been attributed to nuclei and nucleoh, and by 

 many they are supposed to be the agents alone con- 

 cerned in the processes of multiplication and reproduc- 

 tion. These bodies are always more intensely coloured 

 by alkahne colouring matters than the otlier parts of 

 the Hving matter or bioplasm, a fact which is alone 

 sufficient to show the difference between a true nucleus 

 or new centre, and an oil globule, which has often been 

 wrongly termed a nucleus or a nucleolus. In certain 

 cases it would appear that as the process of formation 

 of new centres, one within the other, proceeds, new 

 powers are acquired, or, if we suppose that all pos- 

 sessed the same powers, those masses only which were 

 last produced retaia them, and manifest them when 

 placed under favourable conditions. 



86, Nuclei and nucleoli do not produce formed 

 materiaL — Although nuclei and nucleoh are bioplasm, 

 they do not undergo conversion into formed material. 

 Under certain conditions the nucleus may increase, 

 and exhibit all the phenomena of ordinary bioplasm — 

 new nuclei may be developed within it, new nucleoh 

 within them ; so that ordinary bioplasm may become 

 formed material, while its "nucleus" grows larger 

 and becomes ordinary bioplasm. The .joriginal nu- 

 cleolus then becomes the nucleus, and new nucleoh 

 originate and make their appearance in what was the 

 original nucleolus. The whole process consists of 

 evolution from centres, and the production of new 

 centres within pre-existiug centres. Zones of colour, 

 of different intensity, are often observed in a young 

 elementary part coloured by carmine ; the outermost 

 or oldest, or that part which is losing its vital power, 

 and becoming converted into formed material, being 

 vei-y slightly coloured, — the raost central part, or the 

 nucleus, aWiovgh furthest from the colouring solution, 

 exhibiting the greatest intensity of colour. 



