OF THE COTYLEDONS. 97 



Mr. Knight denominates it the germen, but 

 that term is appropriated to a very different 

 part, the rudiment of the fruit. The expand- 

 ing Embryo, resembling a little feather, has 

 been for that reason named ty Linnoeus Plu- 

 mula ; it soon becomes a tuft of young leaves, 

 with which the young stem, if there be any, 

 ascends. Till the leaves unfold, and some- 

 times after, the cotyledons, assuming their 

 green colour, perform their functions ; then 

 the latter generally wither. This may be 

 seen in the Radish, Lupine, Garden Bean, 

 and various umbelliferous plants, in all which 

 the expanded cotyledons are remarkably dif- 

 ferent from the true leaves. Such is the ge- 

 neral course of vegetation in plants furnished 

 with two cotyledons, or dicotyledones; but I 

 have already mentioned a very distinct tribe 

 called monocolyledones, having but one. These 

 are the Grass and Corn tribe, Palms, the 

 beautiful Orchis family, and many others. 

 In these the cotyledon, or body of the seed, 

 does not ascend out of the ground, and some 

 have considered them as having no cotyledon 

 at all. See Mr. Salisbury's paper in the 

 Transactions of the Linnean Society, v. 7> 



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