THE BEGINNINGS OF LIFE. 191 



production, the mother-cell of new individuals; the 

 germinal vesicles forming in it are the real rudiments 

 of the new individuals, the unicellular germs of new 

 plants. They are formed already before the period of the 

 scattering of the pollen, as free nuclei originating in the 

 upper part of the embryo-sac (the end turned to the 

 apex of the nucleus and the micropyle), in which the 

 protoplasm is principally accumulated. Around these 

 nuclei soon appear sharply defined masses of contents, 

 which are, as it were, cc cut out " of the general mass of 

 contents of the embyro-sac. The number of germinal 

 vesicles is mostly three, rarely more. . . . Ordinarily 

 only one of them becomes developed into an embryo, 

 this outstripping the others in growth even before 

 fertilization or the latter even die away and dis- 

 solve about that epoch.' After mentioning the mode 

 in which it comes into contact with the pollen tube, 

 Braun says: c ln other respects the germinal vesicle 

 remains wholly free during its development into sus- 

 pensor (vorkeim) and embryo; becoming developed 

 without any connection with the other phenomena 

 of cell formation in the embryo-sac ... so that it 

 affords us, not merely in its present formation, but 

 also in its further behaviour, the example of the freest 

 and most independent cell-formation which the plant 

 exhibits.' During the process of formation of the 

 germinal vesicles and certain transitory cells at the 

 other end of the embryo-sac, this latter as a whole 

 seems to retain its vitality ; its primary nucleus usually 



