60 PROCEEDINGS OP THE AMERICAN ACADEMY 



this. After the stage represented in Figure 20, the development be- 

 comes hard to trace. In the next one figured (Fig. 21), the cells b, b', b", 

 etc., are probably to be compared with those indicated by the same let- 

 ters in the previous figure, while c is an undeveloped terminal cell 

 before noticed. The cells b', b", etc., have increased enormously in 

 size and in number as well. They have given rise to many smaller 

 cells the fate of which seems probably to be the formation of the 

 cystocarp proper. The course of growth becomes now even more 

 obscure. The cells in the neighborhood of the young cystocarp be- 

 come complicated in the growth of the wall, and effectually hide the 

 changes which at this time are affecting the cystocarp proper. It 

 seems probable from what was seen that the cells b, b', b", etc., start 

 up another growth, and, budding outwards, form, with the surrounding 

 cells whose growth has been already mentioned, the wall of the tabu- 

 lar cells found in the ripe fruit. Tiie small cells first formed from the 

 activity of the cells b, b', b", etc., are enclosed in this mass, and develop 

 into the spores and spore-bearing cells. It is to be regretted that the 

 material was so scanty for this work. A search will be made next fall 

 earlier in the season, to find if possible more trichogyne-bearing fronds, 

 and an attempt made to determine more definitely the development of 

 the fruit. 



Up to the present time the relationship of C. Polysiphonice to the 

 rest of the Florideae has been very uncertain. Heretofore, it will be 

 remembered, nothing but tetraspores has been described. In his list 

 of the Florideae, Schmitz places it among the Gelidiacese with Bin- 

 derella in the sub-order Binderelleae. His reason for placing it in 

 the Gelidiaceae is presumably on account of its general likeness to 

 Harveyella mirahilis (Reiusch), Schmitz and Reinke, which in the 

 same list is placed in a separate sub-order, Harveyellese, next to the 

 sub-order to which Choreocolax is assigned. Others have followed 

 him in this arrangement, but no one, so far as I know, has placed 

 C. Polysiphonice in any other order of the Floridese. In view of what 

 has been described in this paper regarding the structure of the cystocarp, 

 this can scarcely be considered to be its true place. The cystocarp of 

 Harveyella is likened by Schmitz, in his note in Reinke's " Algen 

 Flora der westlichen Ostsee," to that of Caulocanthus, a resemblance 

 which would place Harveyella without doubt among the GelidiaceiB. 

 It certainly seems impossible to consider the cystocarp of Choreocolax 

 Polysiphonice as closely related to that found in the GelidiaceaB. It 

 lacks the most essential feature of similarity to the Gelidiaceoe in the 

 absence of the complicated axial placenta which characterizes that 



