EUROPE AND NORTH AMERICA. 25 
CHAPTER V. 
ARRANGEMENT OF THE SPECIES. 
Ir is always convenient to distribute the species of a genus into 
groups or sections, especially when they happen to be numerous 
and difficult of diagnosis ; this has been attempted with respect to 
the Sfhagna in various ways by different authors, and it may be 
of advantage to present an outline of each of these. 
BriveEL, in his Bryologia Universa (1826) arranged his sixteen 
species as follows, classing them as Musci Evaginulatt Cladocarpi :— 
1. Ramuli distinctly fasciculate. 
a. Leaves broader, rather obtuse. 
S. cymbifolium tenellum, squarrosum, contortum, subsecun- 
dum,immersum, oblongum, macrophyllum, denticulatum. 
6. Leaves narrower, rather acute. 
S. capillifolium, recurvum, cuspidatum. 
2. Ramuli indistinctly fasciculate. 
S. compactum, ericetorum, condensatum, subulatum. 
C. MULLER, in his valuable Synopsis Muscorum (1848), made a 
great advance on the writings of previous authors by introducing 
the cell structure of the leaves into the specific character of these 
mosses. He points out the differences in the leaves of the stem, 
branches, and peduncle, and the presence or absence of spiral 
fibres in them. 
1. Leaves without annular fibres. 
S. sericeum, macrophyllum. 
2. Leaves with annular fibres. 
a. Leaves rounded at apex. 
S. cymbrfolium, &c. 
6. Leaves truncate. 
* Peduncular leaves without spiral fibres. 
S. molluscum, squarrosum, cuspidatum, acutifolium, &c. 
** Peduncular leaves with spiral fibres. 
S. laxtfolium, compactum, molluscoides, subsecundum, Sc. 
All the species are said erroneously to be dioicous. 
