The Water Tubes of Conocephalum conicum. 
By Agnes Fry. 
AMONG the Liverworts some, e.g., most Ricciaceae, have the 
fructification concealed in the thallus : but the far larger 
number bear it on a stem — of one sort or another. In Mosses, 
except the Sphagna, the seta belongs to the sporophytic genera- 
tion : in some Liverworts this is also the case, as in the great and 
preponderating order of Jungermaniales. In this case the seta is 
often a white, almost translucent thread, consisting of long cells 
of very rapid growth. By the banks of little streams in late 
spring one may see the shining stalks of the withering fructifica- 
tion of Pellia epiphylla, overborne by their own slight weight, 
shewing of what a limp texture they have been built. But in 
the family of Marehantiaeeae it is the oophytic generation which 
supplies the stem — in one of two ways. In Marchantia 
polymorpha, offshoots of the thallus arise like stalks and cany 
the archegonia and antheridia aloft. But in Lunularia and 
Fegatella, the archegonia are seated under little knobs borne on 
the thallus, and after fertilization the stalk grows up. Thus 
fertilization not only creates a new generation but reacts strongly 
on the old — as in manifold other cases in the vegetable world. It 
is, however, generally for the sake of several sporangia that this 
effort is made, though in Lunularia cruciata I have found a well 
developed seta bearing a single fertilized archegone. The sporo- 
phytic stem, on the other hand, never bears more than a single 
sporangium. There are other marked differences between the 
two : the oophytic stems are so far as I have seen of slower 
growth, firmer texture and greener colour, and have often an 
epidermal layer of small cells. In several cases they are note- 
worthy for their strange system of water-tubes. 
It is well known that in Marchantia polymorpha each arm of 
the carpophore originates hairs in its tip : these pass down the 
stalk by one or other of two curiously constructed pipes and 
so reach the soil. The hairs are hollow and studded internally 
with little peg-like excrescences. 
Less attention has been given, however, to the water system in 
Conocephalum conicum, which will be understood by a reference 
to Fig. i. 
Not only do hairs pass down the firm stalk which enfolds them 
near its centre (see Fig. 2) but hairs of the same kind hang down 
from the arm-pit between the stem and the pendant sporangia : 
these, however, do not reach the ground, but serve perhaps by 
their mucilaginous nature to keep the sporangia from drying too 
quickly. The most noticeable feature of the system, however, 
does not appear in Fig. 1, but is best explained by a horizontal 
section taken across x — y, where it is seen that the hairs do not 
pass straight down the tube but first wind round the tops of 
the stem like a turban. 
