500 



racters, on which to found a sufficient number of distinct 

 and very natural genera. Even that author, in the lec- 

 tures before us, records that some genera have a three- 

 leaved calyx, others none at all ; some have a corolla of 

 three, others one of six, petals ; most have six stamens, 

 some three, others nine, while the Nipa of Thunberg has 

 only one. The germens are three in some, solitary in 

 others, and the style and stigma are subject to like diver- 

 sity in different genera. The fruit is in some, as the 

 Phoenix dactylifera, or Date, a single drupa, in others 

 composed of three; in some, like the Cocoa, a nut with a 

 coriaceous coat. The seeds are mostly solitary, but in 

 several instances two or three in each fruit. Hence, while 

 the fructification affords sufficient materials for discrimi- 

 nating genera, Linnaeus observes that no common charac- 

 ter, exclusively descriptive of the whole order, can be 

 founded upon it. The reader will find the essential cha- 

 racters of his genera in our Vol. IV. 288. His Zamia, 

 concerning which he avowed considerable doubts, chiefly 

 because it wanted a spat ha, is now by common consent 

 among botanists, removed either to the Ferns, or to an 

 intermediate order between them and the Palms, to which 

 also Cycas belongs. The technical characters which have 

 induced this alteration, are confirmed by circumstances 

 attending the habit and qualities of these genera. 



At the end of his proper Palmes, Linnaeus subjoins in 

 a distinct section, three genera, which he was doubtful 

 whether to leave there, or to establish as a distinct order. 

 These are Stratiotes, Hydrocharis, and Valisneria. He 

 remarks in his lectures that " they have a spatha ex- 

 tremely like the palms ; a calyx of three leaves, and a 

 corolla of three petals; leaves perennial and evergreen, 

 folded when they first come forth. Hydrocharis cannot 

 be separated from Stratiotes, nor Valisneria from Hydro- 

 charis. They produce their leaves crowded together at 

 the base, like Ferns. Although their strict affinity with 

 the larger Palms of India cannot be demonstrated, thev 



