518 LIFE-HISTORIES 
Fic. 341, I.—Umbrella-liverwort. Female plant (4), bearing archegonia- 
carriers (archegoniophores). (Atkinson.) 
tophyte develops from a spore in much the same way as happens 
with the other liverworts described. Even more than in Riccia it is 
like the thallus of Coleochzte, notably in possessing but a single 
chromatophore in each cell, and in having no trace of pseudo-leaves 
(Fig. 343). The gametangia are completely embedded in the thallus 
(Fig. 344). The embryo (£) develops a somewhat expanded foot 
which serves to hold the slender sporophyte in an upright position, 
and functions also as an organ of absorption. As the sporophyte 
continues to grow, however, it is plain that scarcely more than 
inorganic materials are taken in; for very soon, above the foot ap- 
pears an elongating zone of tissue containing much chlorophyll; 
and this enables the sporophyte to photosynthesize and so, unlike 
our other liverworts, to be almost self-supporting. If an Anthero-. 
ceros sporophyte should ever develop a root it would no longer 
need to be even a partial parasite, as now, but could lead an entirely 
independent existence. The elongating region connecting the cap- 
sule and the foot is morphologically a shoot, and thus we have in 
this little plant the beginnings of a differentiation into three mem- 
bers—sporangium, foot, and shoot. At the center of the shoot and 
