THE CELL DOCTRINE. 49 



dation of the ovum as hithei-to supposed. It ceases 

 to be pellucid." And on page 531, "The germinal 

 vesicle fills with cells, and these become filled with 

 the foundations of other cells ; so that the germinal 

 vesicle is gradually rendered opaque." 



He \also describes in this series, in great detail, the 

 mode in which these cells are produced from ' the 

 germinal spot, which he considers in the light of a 

 nucleus to the germinal vesicle. Part II, 1839, p. 

 360. And though the minute details may not pre- 

 cisely accord with those of the most recent observa- 

 tions, the correct idea is clearly grasped. In fact, it 

 may be said that in minuteness of detail alone does 

 he differ from later observers, and had he simply 

 stated that the young cells arise from the nucleus or 

 nucleolus of the parent cell, he would accord pre- 

 cisely with the most recent observers. But he is, if 

 possible, even more explicit when he says, " The pro- 

 cess inherited from the germinal vesicle by its off- 

 spring, reappears in the descendants of these. Every 

 cell, whatever its minuteness, if its interior be dis- 

 cerned, is filled with the foundations of new, cells, 

 into which its nucleus has been resolved." Again 

 he says,* " Schleiden has seen the nucleus undergoing 

 such changes (division), but failed to recognize them." 

 And finally, in " Philosophical Transactions " for 1841, 

 pp. 207-8, we have the following striking paragraphs, 

 which would seem also to correct some previous 

 errors : 



" § 77. I am very much inclined to believe, that 



* Barry, Philosophical Transac, 1840, p. 348, § 385. 

 5 



