GERMINATION. 133 



one week ; hyssop, one month ; parsley and celery, 

 from six to nine weeks ; the peach and almond, one 

 year ; and the rose, hazel, and cornel, two years. 



Phenomena of Germination. 



The first apparent change in a seed that has begun 

 to germinate, is its obvious enlargement, and the soft- 

 ening of its shell, which ultimately bursts. Whenever 

 the embryo begins to grow, it is termed the plantlet, 

 and consists of two parts, one descending, and another 

 ascending : the first being the embryo root, the second 

 the embryo stem. As soon as the embryo stem or 

 gemlet has reached the open air, its leafits are ex- 

 panded, and begin to perform all the functions of 

 leaves. 



In the meanwhile the shell of the seed prevents the 

 access of too much water, which might, as it were, 

 drown the young plant, and hence Du Hamel found 

 by experiment, that seeds when stript of their shell 

 germinate badly, if at all. The seed-pulp, again, 

 which is nothing more than what remains of the liquid 

 in the cavity where the embryo was developed, being 

 evaporated till it becomes a solid (though this, as in 

 the milk of the cocoa nut, is not always quile effected), 

 is again diluted with the absorbed water, and serves 

 to supply nourishment. This is the case whether 

 the seed-pulp be included or not in the seed-lobes, 

 which it is only necessary to water sufficiently in 

 order to see the whole grow, as was proved by the 

 experiments of Desfontaines, Thouin, Labillardiere, 

 and Vastel. 



