[VOL. 2 

 334 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



(Schmitz, '83). Recent cytological work on the red algae has 

 not confirmed this theory, but, on the other hand, has discred- 

 ited it, since in the cases examined the diploid nucleus of the 

 ooblastema filament and the haploid nucleus of the auxiliary 

 cell are said to repel each other and no fusion between them 

 occurs. It should be emphasized that the fusion of the oobla- 

 stema filament and the auxiliary cell is a fusion of a diploid 

 structure with a haploid one, that it is probably of a nutritive, 

 or parasitic, nature comparable to the fusion of the moss 

 sporogonium with the tissue of the gametophyte, a physiolog- 

 ical, nutritive requirement in the absence of other means of 

 nourishing the moss sporogonium. The fusions occurring be- 

 tween cells of the same ascogenous hypha are fusions between 

 cells of the same phase and serve to bring into association 

 nuclei of more or less remote ancestry, but each endowed with 

 the same number of chromosomes (probably the Ix number). 



Thus, while there are somewhat analogous variations in the 

 splitting up of the ascogonium in the sac fungi, and of the car- 

 pogonium in the red algae, with progress in the direction of 

 increasing the output of spores, it seems fair to conclude, that, 

 so far as the evidence at present in hand is concerned, the rela- 

 tion between the fusion of ooblastema filaments and auxiliary 

 cells in the red algae, and those between the ultimate and an- 

 tepenult cells of the ascus hook (of the ascogenous hyphae), 

 however interesting it may be, has no phylogenetic signifi- 

 cance, and is at best a rather strained parallel. 



Ascogenous hyphae, gonimoblasts, ooblastema filaments, the 

 several fertile cells of certain ascogonia which communicate 

 by resorption of the intervening septa, the fused procarp, may 

 be considered as morphological equivalents, as suggested by 

 Dodge ( '14, p. 174), but there is no evidence of a phyletic rela- 

 tion between the ascogenous hyphae and fusing ascogonial 

 cells, and their morphological equivalents in the red algae. 

 They illustrate different modes of increase of spore output by 

 splitting up of the oogonium. 



NOTE II 



The fundamental difference in the method of development of 

 ascospores and carpospores is one of the great barriers in the 



