1896] PROCARP AND CYSTOCARP OF PTILOTA 357 
numbered eleven in the figures because it is usually the eleventh 
cell of the axial siphon of the procarpic branch. 
DEVELOPMENT OF THE GROUP OF PROCARPS. 
The group of procarps is always situated at the tip of a 
procarpic branch. The number is somewhat variable, but 
typically five. In order that the reader may follow more readily 
the account of the development of this structure it will be best 
to describe first the appearance of mature specimens. It is sug- 
gested that he glance at fig. ro where an adult group of procarps 
is shown. 
There appear in this figure five trichogynes (numbered 11, 10’, 
10°", 10'’ and 10’’’), each of which terminates a short branch 
consisting of three or four cells. Three of these branches are 
figured; the other two could not appear in this view. Each 
branch with its trichogyne is a procarp. Three of the procarps, 
those numbered 11,10’’, and 10'’’, are solitary. The other two 
procarps are peculiar in that they form a pair united together at 
the basal cells. The three lower cells of the solitary procarps 
and one of the basal cells of the pair are all united to the 
terminal segment of the procarpic branch (fig. 10, no. 10). The 
Procarps may then be said to form a group around this terminal 
segment. 
The union between the basal cells of the procarps and the 
terminal segment of the procarpic branch is effected by the 
Strands of protoplasm so generally found between the cells of 
lorideze, 
Bearing in mind the structure of the tip of an adult procarpic 
branch we may now consider the development of the group of 
Procarps. A transverse division of the terminal cell of the pro-” 
carpic branch (jig. 2, cell 10) initiates the development of the 
8toup of procarps. The division is somewhat oblique, so that 
the new terminal cell (fig. 3, cell 11) is pushed over towards the 
4Xis of the pinna, and the curvature of the procarpic branch is 
thus made more pronounced. This division is really simply a 
Continuation of the apical growth of the procarpic branch, but 
