186 A NEW ORDER OF ALG. 
a whole cell, and only appears in the form of a basal protuberance 
from the mother-spores; while in P. Cleveana it is occasionally not 
gessloned at all. 
The anatomical elements consist of vegetative cells and spore-cells. 
en 
€ either intercalated (‘ enclosed”) or terminal, usually « 
cylindrical i ch 0 in-walled without layers; wit 
arietal layer Nees and a large central vacuole.. Their breadth 
varies fr ngth is erally 5-20 times the 
b n further ex xXamining the contents, it is seen that some of 
the cells ns a layer of chlorophyll-granules, the continuity of which 
is usually interrupted in certain parts, and sometimes to such a degree 
See longer), or else they are twisted and usually branched above, 
what the author calls “‘helicoid” cells. These helicoid cells 
) 
e@qualis. As they are filled wi ehlonophi they must have an assimi- 
se function ; but their form a a modification of their membrane 
the bringing forth of prolific cells.” The cell (only proaonaly a 
part, then the protoplasm in this part is increased by apposition 
ie within s we cost of the protoplasm in the lower deta and 
otha ore, sometimes in specimens of P. Cleveana 
where no rhizoid part is developed, a spore may occupy the same a 
the mother-spore, and possess the same membrane as its paren 
cept at its upper part. 
The “ prolific ” cells are borne in most cases by sterile individuals ; 
they are nothing more than ordinary cells packed with starch-grains, and 
being only provided 
aperiod of rest. They become disunited from the decayed elements in 
_ connection with ahah they were Rite’, but ne: isolation is not so 
