THE SPERMATOPHORE IN ARENICOLA 1027 
With such a position in mind, I have a right to take evidence 
on the independence of reduction phenomena and the alternation 
of generations from the algae and protozoa. Moreover I have 
the precedent set by eminent botanists who use Coleochaete, 
Fucus, Polysiphonia, etc., as examples of the alternation of gener- 
ations in the algae and base their theories of the rise of the phe- 
nomenon on such algal evidence. 
Karsten has shown that the mitoses in the zygote of Spiro- 
gyra are reduction mitoses. The same is true of the Desmidaceae. 
These mitoses occur, of course, after the fusion of the egg and 
sperm. In Fucus, reduction occurs in the division of the anther- 
idial and oogonial initials; in the case of the egg, the reduction is 
three mitoses prior to fertilization. (Yamanouchi.) In the Dic- 
tyotaceae, the cells of the tetrasporangium are the seat of the 
reduction division (Williams). Yamanouchi has shown that in 
Polysiphonia it is in the division of the tetraspore mother-cells 
that reduction occurs, while Wolfe claims that in Nemalion reduc- 
tion occurs at the time of carpospore formation. Davis is so 
impressed with the fact that among the algae reduction occurs 
at so many different phases of the life history that he concludes 
that the phenomenon has a multiple origin. He says: 
All of these cells in being the seat of reduction mitoses are analogous 
to the spore mother cells of archegoniates, but that would not warrant 
their being considered homologous with the latter structures. There is, 
on the contrary, good reason to believe that, in plants, reduction phe- 
nomena became established as features in the life histories of a number of 
groups quite independently of one another, as the evidence indicates was 
also true of the processes of sexual evolution and the differentiation of 
the sporophyte generations. (Am. Nat. 43: 109). 
Similarly among the protozoa we find the reduction phenomena 
occurring at various times. In Adalia (Siedlecki) and Monas 
(Prowazek) reduction occurs by the formation of chromidia in the 
gametes before they unite. Neresheimer and Metcalf find that 
in Opalina reduction occurs before the gametes form. Schaudinn 
has shown that in Actinophrys the cytoplasm of the conjugating 
individuals unites and then a reduction of the nuclei occurs. 
JOURNAL OF MORPHOLOGY, VOL. 22, No. 4 
