244 BOTANICAL GAZETTE [octonze 
within the cellulose walls of the gametocysts. This is far from a 
simple sexual condition, and it is a great mistake to present these 
types as illustrations of primitive sexuality. It is possible that the 
Conjugales have come by way of the unicellular forms related to the 
Volvocaceae, whose cells adopting quiescent habits gave rise to the 
desmids, through which the filamentous Zygnemaceae and Mesocar- 
paceae may have been derived. In many-of the desmids the gametes 
escape from the gametocysts to fuse as naked masses of protoplasm. 
The retention in the Zygnemaceae and Mesocarpaceae of these 
gamete protoplasts within the gametocyst, and the consequent fusion 
of sexual cells surrounded by a cellulose wall is a peculiarity identical 
in this respect with the fusion of coenogametes in the Mucorales, 
Peronosporales, and lower Ascomycetes, and is evidence of a highly 
specialized sexual condition. 
In the Rhodophyceae the spermatocysts have the peculiarity of 
producing each a single non-motile sperm, and the oocyst (carpog? 
nium) develops a long filamentous receptive outgrowth, the trichogyné, 
surrounded by the cell wall, with which the sperm fuses. There 1s 
here, therefore, as in the filamentous Conjugales described above, the 
fusion of gamete protoplasts while still surrounded by their respect® 
cell walls. Eliminating this peculiarity and the production of non 
motile sperms, the sexual organs of the red algae appear to bes 
to those of Coleochaete. There are some possibilities, howevel, 
which may complicate the problem of the classification of the sane 
organs of the Rhodophyceae, and may relate it to the puzzling siaiik 
tions in the Laboulbeniaceae and lichens. _I refer to the presene® 
trichogyne nucleus in Batrachospermum reported by my: self, and 
binucleate sperms described by SCHMIDLE (’99). We may find se 
and in other red algae peculiarities with direct relationships to the 
fungal groups mentioned above. 
The Charales present extraordinary conditions. The female 
organ is apparently an oocyst, surrounded, however, 
envelope of investing filaments; while the male organ 1 
and consequently is not a spermatocyst, but falls i have 
group of sexual organs, although it can hardly be suppos aja ise 
genetic relation to these. The spermatangium (anthem ea 
Charales is certainly one of the puzzles of plant morphology: 
