434 BOTANICAL GAZETTE [DECEMBER 
is comparable to the sporophyte generation of the higher plants. 
At that time he expressed his opinion definitely that the tetraspore is 
a special form of reproductive cell, comparable to brood cells or gem- 
mae, and with no fixed place in the life history. However, during the- 
last year (56, p. 273) he has admitted the possibilities of reduction 
phenomena during tetraspore formation. 
Davis (24, pp. 467, 471) in the same year definitely suggested 
the probability that reduction phenomena would be found in the 
tetraspore mother cell. 
WILLIAMs (81) discovered chromosome reduction during tetra- 
spore formation in Dictyota, which led him to conclude that the 
tetrasporic plant in Dictyotaceae is a sporophyte generation derived 
from the fertilized egg. 
Wo tre (86) showed for Nemalion that the cells of the cystocarp 
have double the number of chromosomes found in the sexual plant, 
thus presenting the first cytological evidence that the cystocarp of 
the red algae is sporophytic in character. He places the period of 
chromosome reduction at the time of carpospore formation, basing 
his conclusion on a count of chromosomes in the mitosis just previous 
to the formation of the carpospores. However, he did not report 
the phenomena characteristic of chromosome reduction, namely 
the period of synapsis followed by the two mitoses which distribute 
the chromosomes so as to give a numerical reduction. 
Recently STRASBURGER (75) has published his views concerning 
the alternation of generations in the brown algae, remarking that 
the tetraspores of the red algae seem to be different from those of the 
Dictyotaceae, and that the place of the chromosome reduction in the 
red algae should be sought elsewhere than at tetraspore formation, 
because some of the red algae develop no tetraspores, but instead 
form monospores. It is true that in some groups of red algae tetra- 
spores are never formed, and in certain of these monospores are 
present. In these cases chromosomie reduction may take place with 
the formation of the carpospores, or perhaps with their germination, 
and the monospore when present may have no vital relation to the 
main cycle of the life history. The group of the red algae is very 
large and contains a great variety of forms, with a wide range in the 
complexity of the cystocarp and the vegetative forms, so that It 1 
