IIEJUVKNESCENCE IN NATURE. 277 



mother-plant, the uppermost in the axial row of cells of 

 the ovule, destined to become the focus of the reproduc- 

 tion, 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, 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 which nuclei soon appear sharply 

 defined masses of contents, which are, as it were, " cut 

 out" of the general mass of contents of the embryo-sac. 

 The number of germinal vesicles is mostly three,* rarely 

 more,! sometimes only two, J and very rarely only one 

 exists, in which case, however, the larger number is indi- 

 cated at the earliest period of formation by their nuclei, 

 two of which disappear again without cells having been 

 formed around thera.^ The newly-formed germinal 

 vesicles are roundish at first, but soon extend longitudi- 

 nally ; at first they are only slightly in contact, but as 

 they increase in size become crowded together more closely 

 in the upper end of the embryo-sac. Ordinarily only one 

 of them becomes developed into an embryo, this out- 

 stripping the others in growth even before fertilisation, || 

 or the latter even die away and dissolve about that 

 epoch. ^ At the period of fertilisation the germinal 

 vesicle destined to development presses its end lying next 

 the micropyle firmly against the inside of the wall of the 

 embryo-sac, against the outside of which the pollen-tube 

 is, applied, which double connection may go as far as 

 actual growing together. In other respects the germinal 



* Hofmeister, 1. c, Sorghum, t. xi, f. 23, 23 ; Canna, t. iv, f. 3, 5 ; 

 Oodetia, t. v, f. 5. 



f L. c, Fankia carulea, p. 16. 



j L. c, Polygonum orientate, t. xii, f. 18^ — 20. 



§ L. c, Agrostemma Githago, t. ii, f. 20 — 23. 



II L. c, Zea Mays, t. xi, f. 4; Qodetia, t. v, f. 5, 6, and 'Botaniscbe 

 Zeitung,' 1847, t. viii, f. 10, {Oodetia.) 



*^ L. c, Canna, t. iv, fig. 6. 



