60 HISTORY OF BRITISH MOSSES. 



advanced student. For scientific purposes tliey are un- 

 doubtedly much superior to the artificial arrangement 

 adopted in the ' Muscologia Britannica/ 



Professor Lindley includes all the true Mosses in the 

 Natural Order " Bryaceaj" (Urn "Mosses), making the " An- 

 dreaceffi/' or " Split Mosses," a separate family of the 

 " Muscal Alliance." These, with tlie other families of 

 Cryptogamia, are part of the " Acrogens*." 



Dr. jMtdler, in his ' Synopsis Muscorum/ makes his first 

 class, " Schistocarpi," the same as Dr. Hooker's Division I., 

 having the " inoperculate theca bursting with longitudinal 

 valves," The second class, " Cleistocarpi," is so denomi- 

 nated from having an " inoperculate theca, opening by irre- 

 gular bursts," as in Phascum and allied genera; and the 

 tliird class, " Stegocarpi," contains of course the great ma- 

 jority of Mosses furnished "vrith the true hd or operculum. 

 This very large family is divided into the two very natural 

 sections — also used by Dr. Hooker — of " Acrocarpous" and 

 " Pleurocarpous" ]\Iosses, or those whose fruit is terminal 

 or lateral, with reference to the branches. When we come 

 to minor divisions of " Tribes" and " Genera," we find a 



* riowcrless plants in which the stems and leaves are distinguishable, in 

 contrast with the " Thallogens," in which they are not so. 



