Allen—Spermatogenesis . and Apogamy in Ferns . 11 
much richer in chromatin content than others. In these denser 
nuclei thirty-two double chromosomes are found. Upon the 
spindle they present a fairly close resemblance^ to heterotypic 
chromosomes. In the second division thirty-two chromosomes 
can again be counted at the equatorial plate stage. Other spore 
mother cells in the same macrosporange remain poor in chroma¬ 
tin content and when they divide, sixteen chromosoms are found 
on the spindle in both divisions. Here the figures are also 
characteristic for heterotypic and homoeotypic divisions. 
Strasburger believes that in these latter cases there is a true 
reduction. Concerning the larger mother cells he believes that 
the synaptic condition from which come the diploid number of 
chromosomes cannot be considered as a true synapsis since the 
chromosomes did not fuse or at least did not remain fused. 
Consequently he concludes that the first division in this case is 
homoeotypic in nature and the second division is an added one 
without homologue in other reduction divisions. 
The result of this varied behavior of, the spore mother cells 
is that we have spores of two sorts—diploid and haploid. 
He holds further that the diploid macrospore develops into 
a gametophyte normal in appearance except that the neck of 
the archegone remains closed and the canal cells do not die. 
Thirty-two chomosomes are preesnt during the divisions iti the 
growth of this gametophyte. The diploid and haploid chromo¬ 
some number in other species of Marsilia are thirty-two and 
sixteen respectively. 
The micro gametophyte of Marsilia Drummondi does not de¬ 
velop normally. Ho antherozoids were seen. The egg de¬ 
velops directly into the embryo without fertilization. Since 
the egg possessed the diploid chromosome number, Strasburger 
does not regard it as a true sex cell and in accord with this view 
the form of reproduction found here is called apogamy and not 
parthenogenesis. Thirty-two chromosomes appear in the vege¬ 
tative divisions of the sporophyte so formed. 
Yamanonchi (104) in 1908 studied apogamy in Nephrodium 
moltei. When conditions for fertilization are supplied, this 
species reproduces normally. The diploid and haploid chromo¬ 
some numbers are one hundred and thirty-two, and sixty-six 
