Cutleria multifida ( Grev .). 
85 
Germination of the Oospheres. 
In all cases, whether in later undoubtedly parthenogenetic 
cultures or in the earlier ones only doubtfully so, germina- 
tion proceeded along lines absolutely identical with those 
described by Falkenberg for the sexually-produced spore. 
The spore secretes a cell-membrane, becomes pear-shaped, 
and divides into a shoot-cell and a first rhizoid (Fig. 11) ; the 
latter elongates and reaches a considerable size if germination 
takes place at the surface of the water, but remains short on 
contact with any foreign body. The shoot-portion of the 
plant gives rise to a filament of a few cells only (6-10) by 
intercalary rather than apical segmentation (Fig. 12), and 
then definitely ceases to elongate ; this being, according both 
to Falkenberg’s and the Plymouth experiments, all that 
remains in this type of germination to mark the primitive 
filamentous condition of the Cutleria (Fig. 12, one week 
old). 
Irregular segmentation commences immediately through- 
out the young plant ; any and ultimately every cell dividing 
repeatedly by walls in different quadrant-planes, until the 
embryo becomes a more or less club-shaped multicellular 
mass of tissue, attached by one extremity and still exhibiting 
radial symmetry (Figs. 12, 13, 14). 
To this stage Falkenberg has given the name of the c Foot,’ 
and it is probably representative, both phylogenetically and 
ontogenetically, of a primitive thalloid condition in which the 
main axis of the plant was radially symmetrical and 
segmented behind the growing region in the regular manner 
seen in such a form as Stypocaulon. When well-developed, 
the foot may form a well-marked tissue-mass (Fig. 14) ; but 
it is often, and this was more general in some cultures than 
others, to a great extent abbreviated in development, 
ultimately giving rise to an embryo which was practically 
dorsiventral throughout (Fig. 16), and identical with the 
oldest embryos obtained by Janczewski 1 in C. adspersa . 
1 Loc. cit. p. 220. 
