Nucleus of the Animal and Vegetable *• Celiy 221 



to be the case ; and here also Professor Goodsir informs me 

 that he adopts my views. 



It may be added, that at a recent meeting of this Society 

 the same talented observer mentioned an observation of his 

 own on some of the poligastric Infusoria, as fully confirming 

 mine, — that the nucleus sometimes passes directly into a spi- 

 ral form while still within its cell. And in the same quarter 

 my observation has been confirmed, — that the spiral is the 

 most primitive of forms. (To this, I have no doubt, is refer- 

 able the spiral form retained through life by some of the 

 lower animals : — for instance, the spiral-shelled Mollusca.) 



In the blood of animals which had been kept for periods 

 varying from 18 hours to two days after 

 death, I found the nuclei of the corpuscles ^°* 



dividing into segments (fig. 32),'* and the >( 

 segments sending out processes; which pro- ^Vy-T >^ ^ 

 cesses, becoming acuminated, passed into ^H 



cilia. The vibrations of these cilia gave to 

 the now star-like corpuscles a locomotive power. This I have 

 observed to be precisely the mode of origin of the mammife- 

 rous Spermatozoa, — each of which is represented by one of 

 the segments in that figure. (The segments and the cilia, it 

 will be seen, are processes from the hyaline. Compare with 

 fig. 8.) 



I believe that when animal and vegetable substances are 

 macerated in water, particles of hyaline (fig. 1), which are 

 the true cell-germs, may assume an independent life in the 

 form of Infusoria ; and thus go far to explain the so-called 

 spontaneous generation. t 



It may be added, as an observation I have not published 

 before, that the markings on the egg-shells of Birds afford a 

 beautiful display of colouring matter, obviously formed in cells, 

 and there seen on a scale so large as to be visible without a 

 magnifying power ; the colouring matter being sometimes of 

 deepest hue in what had been the situation of the nucleus, 



* Phil Trans., 1841, Plate XXII., Fig. 105, y. 



t Oxi this subject see my views more at length, iu No. Ixx. of this Journal 

 (October 1843), pp. 219, 220. 



