214 SEAWEEDS 
Gelidice. 
The gonimoblast consists of much-extended, diffuse 
filaments which frequently unite with the thallus 
cells, these being in some cases specially developed 
as auxiliary cells. The terminal, carpospore-bearing 
cells occur in fertile sori or groups (like the hymenial 
layers of fungi), and bear the spores singly as a rule, 
rarely in short chains. The main difference between 
this type and the preceding families lies in the fact 
that this gonimoblast is not nourished exclusively by 
the fertilised carpogonium, but attaches itself in this 
growth to other cells, viz. cells of the thallus-tissue. 
A single gonimoblast is produced as a rule, but it 
ramifies abundantly, and lays under contribution 
either cells of the central axial row or the small- 
celled tissue that envelops it. From the ends of 
the branches of the gonimoblast the carpospores are 
produced, as described. During the branching of 
the gonimoblast a local enlargement of the thallus 
occurs, and within this the cystocarpic fruit is 
developed, with no special wall of its own, and 
bounded only by the sterile thallus-tissue. An 
opening is formed by the separation of the peripheral 
cells, through which the carpospores escape. In 
Vaccaria the carpogonial branch exhibits a difference 
from the ordinary type. From the cells composing 
this branch short lateral branches arise, and the whole 
constitutes a definite system of cells. The carpo- 
gonium itself is relatively a small one, but before 
emitting the gonimoblast it unites with one of the 
