SECT. II. PHYSICAL PHENOMENA. \Q 



also, no doubt, by the foramen, where it exists, and 

 partly by the surface of the envelopes. 



But how is the moisture, which is absorbed at 

 the scar or otherwise, transmitted to the plantlet, 

 the radicle of which exhibits the first certain 

 symptoms of germination ? Does it enter the plant- 

 let immediately ? or is it conveyed to it through 

 the medium of some particular channel ? It was 

 early suspected that the moisture destined to give 

 developement to the plantlet first passes through 

 the medium of the cotyledons. This opinion was 

 founded upon the apparent adaptation of the co- 

 tyledons for the purpose both of absorbing and 

 transmitting moisture, in consequence of their soft 

 and fleshy texture, and of the vessels dispersed 

 throughout their substance, which, after uniting at 

 last into one bundle, are incorporated into the very 

 body of the plantlet, and are by Grew regarded 

 as the seminal root.* They are sometimes visible 

 even before germination has taken place ; but par- 

 ticularly after it has made some progress. On the 

 surface of the transverse section of the lobes of the 

 Bean, after it has been well soaked in water, or 

 after its germination has been begun, they appear 

 in the form of small spots or specks ; and on the 

 surface of the longitudinal section, or even on the 

 natural and inner surface of the lobes, their va- 

 rious ramifications may.be traced, fewer as they 

 approach their point of union with the radicle, and 



* Anat. of Plants, book i. sect. 24. 

 C 2 



