264: CERATOPHYLLACEiE. [Diclinous Exogens. 



inferior radicle is with most of the Urtical AlHauce. Such being the case, it seems to 

 me that mitil some better suggestion shall have been offered than that of stationing 

 Hornworts near the Gymnospemious Conifers, they may be regarded as anomalous 

 plants of the Urtical Alliance. 



A smgular view is that of Dr. Asa Gray, who would place Ceratophyllum near 

 Nelumbium, because of its highly developed plumule, for it would be difficult to point 

 out any other resemblance ; to this opinion he has been led by the account of the 

 development of the embryo given by ^I. Adolphe Brongniart Ann. Sc. 12. 253, which 

 is only in part correct. 



Found m ditches in Em'ope, North America, Northern Asia, Senegal, Barbary, and 

 India. 



These plants have no Imown use : they have sometimes the heavy smell of Chara. 



GENUS. 



Ceratophyllum, L. 



Numbers. Gen. 1. Sp. 1. according to Schleiden ; 6 accordmg to Chamisso. 



ChenopodiacecB. 



Position. — Urticacese. — Ceratophyllace^. 



HaloragecE. 



