120 BOTANICAL GAZETTE [FEBRUARY 
would give much the appearance described by LINDENBERG. We 
know now that the sporophyte has no Hiille or sheath. 
SPOROPHYTE. 
The development of the sporophyte agrees with the account given 
by CAMPBELL (3) for Riccia and by GARBER for Ricciocarpus natans. 
The first division is usually transverse but may be oblique (jig. 21). 
The next wall may be perpendicular to the first so as to form a quad- 
rant (fig. 22), or parallel to it, producing a row of cells. Divisions 
take place in all directions after this until an almost spherical mass 
containing several cells is formed. Then the amphithecium becomes 
distinct. as a single layer of cells enclosing the spore producing cells. 
The growth takes place rapidly but the divisions of the cells are not 
simultaneous, usually only a few dividing cells being found in a 
sporophyte. 7 
The sporophyte continues its growth until a solid mass of three 
to four hundred cells is produced. Then the calyptra and amphi- 
thecium expand and the spore mother-cells becoming free separate 
from one another and become rounded. From the surrounding 
cells, which are richly stored with food, there is secreted a large 
amount of nutritive material which fills the space around the mother- 
cells, giving them favorable conditions for growth (figs. 25, 206). 
The spore mother-cells increase rapidly in size and again fill the 
cavity. That part of the nutritive material not absorbed by the 
spore mother-cells is pressed into thin plates between them. This 
material takes .a deep blue stain with gentian violet. A fuller dis- 
cussion of the spore mother-cells and of their division to produce 
the spores will be given in another place. 
Before the spores are mature the inner layer of the calyptra 
collapses. The amphithecium is distinguishable until the spores 
are almost mature. The outer layer persists but the cells are usually 
shrunken. The contents of these cells is no doubt used up to supply 
the growing spores with nourishment. All of the spore mother- 
cells produce spores, there being no sterile tissue in the form of elaters. 
In discussing the simple form of sporophyte of Riccia, GARBER 
considers that the absence of sterile tissue is to be associated with 
the habit of the plants; since there is not much chance for the attach- 
ment of an independent sporophyte, there is no sterile tissue in 
