GRYPTOGAMIA. 40J 



4. Algce. Flags. In this Order the herbage 

 is frondose, sometimes a mere crust, some- 

 times of a leathery or gelatinous texture. 

 The seeds are imbedded, either in the frond 

 itself, or in some peculiar receptacle. The 

 - barren flowers are but imperfectly known. 

 Here we find that great natural Order, 

 comprehended by Linnaeus under one ge- 

 * nus by the name of Lichen, the fructifica- 

 tion of which, for the most part, consists 

 of a smooth round disk, flat, convex, or 

 concave, with or without an adventitious 

 border, in the substance of which disk the 

 seeds are lodged. In some others they 

 are placed in powdery warts, or in fibrous 

 receptacles. The barren flowers are sup- 

 posed to be powdery also, very much like 

 those of Junryermannia. See EngL Bot, 

 t. 126, and various other parts of that 

 work, where a great number of species are 

 figured. The whole tribe has been much 

 investigated, and attempted to be divided 

 into natural genera founded on habit, by 

 Dr. Hoffmann of Gcettingen, whose figures 

 are perfect in their kind. But a more 

 complete scheme for reducing this family 



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