CRYPTOGAMIA. 3^1 



and experienced hand, according to the principle I 

 have suggested, of retaining in them such genera only 

 as have a permanent difference in the accessory as 

 well as the essential parts of their flowers, their bulk 

 being by such a reformation much diminished, it 

 migt be advisable to reduce them to one Class, in 

 which the slender remains of Polygamia might com- 

 modiously be included, and the title of such a Class 

 should be Diclinia^ expressing the two distinct seats 

 or stations of the organs of fructification. 



Class 24. Cryptogamia. Stamens and Pistils either 

 not well ascertained, or not to be numbered with any 

 certainty. Orders 5. 



1. Fllices. Ferns. The parts of their flowers are al- 

 most entirely unknown. The fructification, taken 

 collectively, and proved to be such by the production 

 of prolific seeds, grows either on the back, summit, 

 or near the base of the frond. Some are called annu- 

 latce, annulatcd, their capsules being bound with an 

 elastic transverse ring ; others thecatce^ or more prop- 

 erly exanmdatiS^ from the wantof such an appendage, 

 of which some of the latter have nevertheless a spu- 

 rious vestige. All the former, and some of the lat- 

 ter, are dorsiferous, bearing fruit on the back of the 

 frond, and of these the fructification is either naked, 

 or else covered with a membranous involucrum. 

 The genera are distinguished by Linnasus according 

 to the shape and situation of the spots, or assemblages 

 of capsules, besides which I have first found it nec- 

 essary to take into consideration the absence or 



