the Cystocarp in Rhodomelaceae. 29 ^ 
The branch destined to bear the cystocarp consists of from 
eight to twelve joints. The first becomes the stalk of the 
cystocarp. The second is the reproductive joint proper, 
giving rise to the greater part of the pericarp, and the whole 
of its contents. The third is included in the cystocarp with 
the products of the second joint, but has no further history. 
All the remaining cells of the filament wither off when fer- 
tilization has taken place, leaving eventually no mark of their 
presence. 
The first joint forming the stalk cuts off from the central 
cell five pericentral cells. Other cells are derived later from 
these, giving rise to a cortex, similar to that which character- 
izes the vegetative parts. Some cells of this number con- 
tribute to form the inferior part of the pericarp. 
The second joint is that from which springs the carpogonial 
branch. Five pericentral cells are here also cut off from 
a central cell. The last formed is ventral, i. e. in the median 
position above. The two pericentral cells on the dorsal side 
divide but slightly. The two cells right and left of these divide 
rapidly (Fig. 10), forming two plates of cells protruding ventrally 
so as to enclose as a rudimentary pericarp the fifth peri- 
central cell. The two lateral convex plates thus arising and 
leaving a median gap above and below have been compared 
to the paired valves of a bi-valve shell-fish. Later on this 
two-sidedness disappears, the wall becoming globular by the 
filling up of the median gaps. The fifth pericentral cell, 
enclosed as thus described, gives rise to the carpogonial 
branch. It forms, moreover, two other branches, a one-celled 
branch in the median position below, and another two-celled 
branch directed laterally upward. The carpogonial filament 
is lateral also, facing the second of the two branches referred 
to above. It consists of four cells and is directed upward. 
The end cell is the carpogonium and is prolonged into 
a trichogyne which passes out medianly above in the gap of 
the pericarp, which is as yet bi-valve (Fig. 1). The carpo- 
gonial branch is curved into a crescent in a plane which is not 
quite median, but the long trichogyne usually lies parallel to 
