382 Mr. llooKr.u'a Observations on Andrcea. ■ 



that thougl), as remarked above, its appearance seems rather to 

 assign it a place with the Ilepaticce, there will nevertheless be 

 found no difficulty to exist in allowing it to continue, as it now 

 senerally stands, among the Miisci. 



The genus by Ehrhart himself was placed in the third order 

 of the 24th class of Linnaeus (the Algce), which at that time 

 contained Avhat are now called Hepaticce. He was, in all proba- 

 bility, induced to leave it there, from a reluctance to make al- 

 terations that did not appear absolutely necessary, and from its 

 affinity to the genus Jungermannia in the same order, without 

 considering the character of this order as given by Linnjeus : — 

 " A plant whose root and stem-leaves are all in one." It is how- 

 ever extraordinary he should have done so, since the definition 

 of the genus Anclrcea, as first drawn out by himself, has so many 

 characters in common with the Musci, and so few that are ana- 

 logous to any thing among the Alga. 



For the benefit of those Avho may not have an opportunity of 

 seeing the Beitragey where it is contained, I will here transcribe 

 this definition. 



" ANDRE^A. 



" Perichatium squamosum. 

 " Squama lanceolatae, carinatse, imbricatse. 

 " Authophorum longitudine perichaetii» 

 " Calyptra conica, brevissiraa. 

 " Stylopodium nullum. 



" Conioecium ohlongum, subtetragonum, 4-sulcatum. 

 " Apophysis turbinata. 



" Valvula quatuor carinatae, angulares, basi apophysi apicibus- 

 conjunctorio adnatse. 



" Suturte 



