CHARACTERS AND DESCRIPTION pso 



OB 



LYELLIA, &c. 



In the tenth volume of the Society's Transactions, I have 

 given a description of Bawsonia} a genus of Mosses having 

 entirely the habit of Polytrichum, but whose peristomium, 

 instead of consisting of a single row of short teeth connected 

 by a horizontal membrane, is composed of an indefinite 

 number of capillary cilia. These cilia, originating both from 

 the inner surface of the capsule, immediately within the 

 orifice, and from the columella itself, form a loose pencil, of 

 which the hairs are sufficiently distinct to allow of a gradual 

 discharge of the seeds. 



The correctness of this account of Dawsonia, especially 

 as to the origin of the peristomium^, and the nature of the 

 supposed columella^ has been questioned by some of those 

 authors, who have since adopted the genus. 



From a careful re-examination, however, I find no reason 

 to alter in any respect the generic character formerly given ; 

 and to the description of the species I have only to add, 

 that the upper surface of the leaves is furnished M'ith parallel 

 lamellae, like those of Folytriclium ; and that the inner 

 membrane of the capsule is, in the early stage at least, pei 

 connected by numerous plicae with those elevations of the 



2 Bridel Meth. Nov. Muscor. p. 205. 



* De la Pylaie in Journal de Botanique appliq. iii. p. 134. 



