376 CHANGES SUCCEEDING IMPREGNATION. CHAP. VIII. 



appearing first in that region where the umbilical 

 vessels perforate the internal membrane, and where 

 the sacculus colliquamenti originates ; not where 

 the umbilical cord enters the testa. Its first for- 

 mation eludes the search of the keenest eye aided 

 by the best glasses. But, by and by, as it aug- 

 ments in size and solidity, it becomes at length 

 visible, in some plants sooner and in others later, 

 after impregnation. In Hdianthus it is perceptible 

 on the third day after impregnation, but in Colchi- 

 cum not till after several months. Its figure is at 

 first globular, its contexture pulpy, and its colour 

 white. It swims in the liquor amnii, from which it 

 derives its nourishment, seemingly unconnected 

 with either the seed or plant ; but immersing itself 

 deeper and deeper every day, and always in such a 

 position as to turn the radicle towards the exterior 

 of the seed, and the opposite extremity towards the 

 centre ; which extremity divides itself into lobes 

 called cotyledons, through which the nourishment 

 of the plantlet passes, or in which it is elabo- 

 rated. At length the chorion is exhausted, and the 

 amnios absorbed or converted into albumen^ and the 

 embryo with its integuments transformed into a per- 

 fect seed. 

 Fecunda- Such are the phenomena, according to the de- 



tion spuri- . . . 



ous or in- scnption or Gaertner,* accompanying or following 

 the impregnation of all flowers producing seeds, 

 except where the fecundation is spurious or incom- 



* De Seaninibus. Jntrod, 



