530 BOTANICAL GAZETTE [DECEMBER 
with the sporophyte. The calyptra is notably smaller than in 
Symphyogyna and Monoclea, presumably because its protective 
function is performed by the perianth. The non-functioning arche- 
gonia are carried up with the tissue of the calyptra but do not per- 
sist long. Only one embryo was seen developing in an archegonial 
group, although it is possible that more than one may be formed, 
as in Symphyogyna aspera. 
The differentiation of the spores and elaters occurs late in the 
development of the sporophyte, and follows precisely the method 
of Symphyogyna aspera, as described by Miss McCormicx (figs. 33- 
38). Material showing the reduction division in the formation of 
spores was entirely absent in the material studied. FARMER (5), 
in his study of this process in Pellia epiphylla and Pallavicinia 
decipiens, noted the presence of a quadripolar spindle in the spore 
mother cell. Moore (10, 11), however, working with Pallavicinia 
Lyellii, failed to find such a condition, but observed that the two 
divisions take place in very rapid sequence, giving the appearance 
of such a spindle as FARMER describes. 
The mature capsule is cylindrical, is inclosed by a sterile wall 
one cell thick, and bears spiral thickenings (figs. 32, 39). The 
sterile cap at the apex of the mature capsule is not so prominent 
as in Symphyogyna, being only 5 or 6 cells thick, and bears no rela- 
tion to the elaters. The mature sporophyte reaches a length of 
40 mm., the capsule being about 3.5 mm. long. Dehiscence is by 
means of 4 longitudinal slits which remain attached at the top. 
The foot is wedge-shaped as in Symphyogyna, but it occasionally 
shows a resemblance to the anchor-like foot of Marchantia (figs. 41, 
42). The mature elaters reach a length of nearly o.3 mm., and are 
furnished with a double spiral band. The spores are about 
se 5 mm. in diameter, the wall being conspicuously reticulate 
fig. 38). 
Summary 
1. Pallavicinia Lyellii belongs to the subgenus Eupallavicinia, 
_ the vegetative body consisting of a single prostrate portion. 
2. The apical cell is of the dolabrate type. Branching is both 
apical and adventitious. , 
