283 HISTORY OF BRITISH MOSSES. 



Mosses. The Fissidens section of the genus Dicranum 

 afford some illustration of a similarity of structure. In 

 both the true Hepatic Mosses it has been remarked, that 

 " the leaves and stems are always of one homogeneous, cel- 

 lular substance, perfectly united and continuous ; and there 

 is never any solution of continuity between those parts, like 

 the fall of the leaf in other plants, at any part of their 

 growth." Thus, like the Mosses, they are sessile, perma- 

 nent, and vary much in form, being ovate, orbicular, wedge 

 and str'ap-shaped, etc. Most of this section of the Jmiger- 

 mannia have leaves, arranged in a bifarious or two-rowed 

 manner; and these are either without folds, or clasp the stems 

 in various ways. In several species the leaves consist of 

 lobes, or divisions, deeply cut, and minutely fringed, forming 

 elegant and beautiful objects for the microscope. Unlike 

 the Mosses, the leaves of this family are entirely destitute of 

 nerves, a character, among others, which shows that they 

 hold a lower rank in the Vegetable Kingdom. In Junger- 

 mannia puhescens, and various foreign species, we find the 

 surface of the frond covered with minute hairs, a character 

 of which we have no example among Mosses. Again, while 

 among these, especially some Ilijpnums, the leaves are often 

 secund, or have a one-sided direction, the Jungermannia 



