Dr. Smith's Inquiry into the Structure of Seeds. 215 



ever. The Cotyledons of Pinus all present their backs to receive 

 the oxygen. 



Some plants appear to be really furnished with one simple Co- 

 tyledon, as Zamia, and according to Gaertner's figures and descrip- 

 tions, the true Scitaminea, as Amomum (his Zingiber), Alpinia, Sec; 

 while Camia seems to have no Cotyledon, but only an Albumen. 

 Can this be true ? and if so, what is the value of such a distinc- 

 tion in a natural classification ? The Liliacece, Palmce, and now 

 the Orchidece, are acknowledged to be Acotyledonous, having only 

 an Albumen ; while the Grasses, so nearly allied to them, have 

 one Cotyledon, for I presume their scale must be admitted as 

 such. Gaertner's phrase of Embryo monocotyledoneus applied to 

 these last-mentioned families may occasion a mistake, which 

 would be avoided by the term Embryo simplex, or indivisus, ex- 

 pressing his idea of the simple figure appropriate to this part in 

 such plants, but which does not prevent its upper extremity 

 being strictly analogous to the Plumula of the Dicotyledones, It 

 seems to me therefore that this learned writer is mistaken in say- 

 ing the monocotyledonous plants never have any Plumula. They 

 have not indeed that feather-like configuration in the ascending 

 point of their Embryo which gave rise to the name, but the or- 

 gan so called is, and must be, present.. To dispute about the 

 term is as little to the purpose as to contend that the Orchidecc 

 have wo pollen, because it is not of a powdery appearance. 



From Mr. Lindsay's account of the germination of Ferns in 

 our 2d Volume, this family must be deemed Monocotyledonous. 

 Their germination seems at first analogous to that of Mosses, 

 as given by Hedwig in his Theoria, but the numerous and 

 branched Cotyledons of the latter overset all analogy, and in- 

 deed all classification of plants by the number of the parts in 

 question. Nothing could be more unnatural than to separate 



Mosses 



