BRYOPHYTES 
initial. The mature archego- 
nium is stalked, with a massive 
venter, a long and often twisted 
neck, and numerous neck canal 
cells (fig. 249). 
Sporophyte. The sporophyte 
(fig. 250) develops at first by a 
series of transverse walls until a 
short filament is formed, which 
later becomes massive by means 
of vertical walls. The upper tiers 
develop the capsule, which is 
organized as in Anthoceros, with 
the endothecium developed as 
the axial columella, with the 
sporogenous tissue cut off as an 
inner layer (becoming four 
layers) of the amphithecium FlG . 24 &. Sphagnum: stem bearing a 
and capping the Columella like terminal cluster of sporophytes, showing the 
a dome, and with a wall of five Position of archegonia. 
to seven layers. These Anlhoceros-\ike features are further emphasized 
by the large bulbous foot and the rudimentary seta, which is only a 
necklike connection between capsule and 
foot, and is often called the neck. Very 
important differences, however, are as 
follows: (i) there is no such development 
of chlorophyll tissue in the wall of the 
capsule as characterizes Anthoceros; (2) the 
neck is not a growing region, and hence 
the capsule does not elongate ; and (3) the 
capsule dehisces by a definite lid (oper- 
culum), which is distinctly a moss character. 
As in all bryophytes, during the develop- 
ment of the sporophyte the venter of the 
FIG. 249.'- Sphagnum: sur- archegonium develops the encasing calyptra, 
face view of three archegonia; which in Sphagnum is ruptured by the 
the middle archegonium shows growing capsule. 
the spiral direction of the cell . . 
rows of the neck. - After A peculiar feature of Sphagnum is the 
SCHIMPER. pseudo podium, which is a structure replac- 
