SL 
oc 
on 
The development and structure of the carpogonial branch 
and of the cystocarp have been treated by Hauprrieiscu 
(1892) and Kyrın (1923). Reference may be made to the 
description of Kyrın. The tri-cellular carpogonial branch 
arises as an outgrowth from a primary cortical cell (supporting 
cell) which becomes multinuclear. Two auxiliary cells are 
usually present the mother-cells of which bud off from 
the supporting cell, but one only is developed after fertiliza- 
tion. After the entering of a sporogenous nucleus in the 
auxiliary cell, a cell buds off from its upper side, and from 
this cell several gonimolobes are produced. The wall of the 
cystocarp has a well developed pore at the top. For more details 
see the papers quoted. 
The tetrasporangia are embedded in the cortex, and form 
groups at the bottom of depressions in the cortex of the younger 
parts of the frond; the sporangia do not project inwards into the 
cavity of the frond (fig. 584). They are tetrahedrally divided. 
The germination of the spores has been studied by KILLIAN 
(1914, p. 246), but owing to difficulties with the cultures he 
f . s 
2 ) 
É | 
x \ 
I 7 
or VA 
A ; | 2 
WR 5 
ip: | 
| Be 
12 
| 
Fig. 584. 
Lomentaria clavellosa. Au- 
gust. Tip of tetraspore-bear- 
ing frond, 30:1. 
was not able to follow the first stages of the development of the germlings. 
The youngest stage figured by Kırrıan is an orbicular disc showing in the middle 
Fig. 585. 
Lomentaria clavellosa. Germlings obtained in cultures. A—C and E—F 8 days old. D 15 days old, 560 : 1. 
D. K. D. Vidensk. Selsk, Skr., 7. Række, naturvidensk, og mathem, Afd., VII, 4. 
75 
