Stems. 
Form and 
Ramification. 
Innovations. 
A >V 
. # 
INTRODUCTION . 
* 
These seem to answer to the “ Radices primaria ,” which Hedwig describes in 
the Mosses, and the “ primordiales" of B ridel : whilst the fibrous ones are the “Radices 
succedanece ” of the same author. The former are thus defined by him : “Quoad originem, 
radices sunt vel primordiales, qute a seminis in plantulam cxplicatione pra;sentes fuerunt, 
vel succedanece., quas caulis parte sua inferiore diversis temporibus emisit. Radix autem 
primordialis, prsesertlm si unica et crassiuscula sit, non raro in ipsum caulem ita con- 
tinuatur, ut vix dignoscere queas ubi hie incipiat, ilia dcsinat.” ( Brid . Muse. Hist. i. p. 6.) 
All the species that I have yet observed to possess “ Radices primordiales ,” are nearly 
erect in their mode of growth, and are found growing in earth, where these roots penetrate 
to various depths, or creep horizontally just beneath the surface. In those species which 
are prostrate in their places of growth, the fibrous roots alone are found ; and, by means 
of these, they are more or less firmly attached to soil of various kinds, to rocks, trunks of 
trees, and decayed wood, or to Mosses, and even other Jungermannias. J . platyphylla, 
and, probably, all the individuals that are so densely imbricated, send forth roots, which 
strike into the leaves of their own stems over which they happen to lie, and from them 
appear to draw nourishment (See Suppl. tab. 3). 
STEMS. 
The stems of Jungermanniae may likewise be separated into two kinds; such as are 
furnished with leaves (the Jungermannicc folioscz of Authors), and the Jungermannia 
frondosce. J. pusilla (tab. 69) and J. B/asia (tab. 82, 83, 84) seem to be intermediate; 
but, in general, the character is very clearly impressed upon the plants, and they may 
be distinguished by their first aspect. 
The first are by far the most numerous in point of species, and are, for the most part, 
cylindrical, or tapering gradually towards the extremity : in J. incisa (tab. 10) they are 
depressed: erect in their growth in J. Hookeri (tab. 54), J. asplenioides (tab. 13), &c. ; 
and procumbent in J ■ bicuspidata (tab. 11), J. byssacea (tab. 12), and many others : simple 
in J. lunceolata (tab. 18), J. excisa (tab. 9), J ■ exsecta (tab. 19) : slightly branched in J.pumila 
(tab. 17), J. pusil/a (tab. 69) : very much branched in J dilatata (tab. 5), J. Mackaii 
(tab. 53), and J. serpyllifolia (tab. 42). 
In general the branches are irregularly scattered; but in J. reptans (tab. 75), J . Woodsii 
(tab. 66), and J. Tamarisci (tab. 6), they are pinnate or bipinnate: sometimes the stems are 
dichotomous, as in J. spinulosa (tab. 14). 
Besides those branches, which, if I may so express myself, unfold themselves with 
the regular growth of the plant, innovations are very frequent upon the stems of Junger- 
mannicz folioscz ; and it is probable, that almost every species, at some or other period of 
its existence, produces them. Instances may be seen in J ■ hyalina (tab. 63), J. compressa 
(tab. 58), J. crenulata (tab. 37), & c. These must be carefully attended to; or, otherwise, 
from the shooting forth of an innovation immediately beneath a calyx, the fructification 
will appear lateral, which is, in reality, terminal. 
What I have said of the stems of the Foliaceous Jungermannicz, applies equally to the 
species frondoscz, except that, in them, the stems, or nerves as they are called in these, are 
Nerve. 
