HEPATIC^. CHAP. III. 



but creeping along ttpon the surface of the soil or 

 substance to which it is attached, and striking root 

 as it extends. Sometimes it is simple, and some- 

 times, as in Jungermannia tamariscifolia, branched 

 or forked. It is also for the most part furnished 

 with a midrib, from the opposite sides of which a 

 number of circular and lobe-like leaflets issue, 

 sometimes in a single and sometimes in a double 

 row, overlapping one another, and assuming not 

 merely a winged, but often a loricated appear- 

 ance. In such species as have no midrib, the 

 herbage consists merely of a cluster of circular and 

 lobe-like substances growing out of one another, 

 and lying flat on the ground, to which they are 

 fixed by fibres issuing from the under side, as in 

 Mar chant ia polymorpha ; a mode of growth in- 

 deed common in some respect to the tribe, the 

 shoots or branches being for the most part closely 

 matted together, and interwoven into flat and dense 

 patches. The structure of the lobes is also ex- 

 tremely beautiful, exhibiting when placed under the 

 microscope, a fine net-work of vesicles frequently 

 transparent. Their colour is generally green, but in 

 Jungermannia dilatata it is of a dark brown, ap- 

 proaching to red. 



SECTION II. 



Reproductive Organs. 



Analogous THE reproductive organs of the Hepaticae, in as 

 Mosses. f ar as tne y are y et known, are pretty much analo- 



