49$ fcRYPTOGAMI/. 



to systematic order lias been recently 

 made known to the world by Dr. Acbarius, 

 a learned Swede^ who in his Frodromus, 

 and Metliodus Lichen um, has divided it 

 into genera founded on the receptacle of 

 the seeds alone. Hence those genera, 

 though more technical, are less natural 

 than Hoffmann's ; but they will, most likely, 

 prove the foundation of ail that can in fu- 

 ture be done on the subject, and the works 

 of Acharius form a new lera in cryptogamic 

 botany. It is only perhaps to be regretted 

 that he has been somewhat too prodigal of 

 new terms, which when not wanted are 

 always a burthen to science, and rather 

 obscure than illustrate it. Thus Hedwig 

 used the term sporangium for a seed-ves- 

 sel, pericarpiiim, in which the learner 

 would seek in vain for any distinction, or 

 new idea. A student might very justly 

 complain if, in a science necessarily so 

 overburthened with words, he were re- 

 quired to call the same part by a different 

 name in every different family. I would 

 gladly tlierefore retain the word frons in 

 preference to the thallus of Acharius, re- 



