Allen-—Spermatogenesis and Apogamy in Ferns . § 
in a few eases are perfect, showing stalk, wall and annulus and 
containing several spores. Gametophytic and sporophytic char¬ 
acters are intimately associated here and the cytological prob¬ 
lems presented are certainly very complex. 
Woronin (100) in 1907 describes apogamy in Trichomones 
Kraussii, Pellia flamens, Notochlaena Eckloniana, N. sinuata 
and Pellaea teriera. Cultures of Pellaea flavens grown in poor 
light or on poor soil show transitions between gametophyte and 
sporophyte .as mixed as those reported by Lang. 
Farmer and Digby (40) in 1907 have described a most re¬ 
markable nuclear migration and fusion in the prothallium of 
an apogamous species of Lastraea which they characterize as 
a vegetative fertilization, and they have traced out the history 
of the chromosome number in several other abnormal types. 
Their results may be summarized as follows: 
1. Athyrium felix foemina var. clarissima Jones. In this 
variety, there are apospory and apogamy. Both the sporanges 
and the archegones are abortive. There is no reduction or 
doubling of the chromosomes, the number, presumptively the 
double number, ninety, is maintained unchanged throughout 
the life history. 
2. Athyrium fdix-foemina var. darissima Bolton. Here 
we have apospory and parthenogenesis. The sporanges are 
always sterile. The double number of chromosomes, eighty- 
four, is present in both gametophyte and sporophyte. In 
spite of the double chromosome number eggs and antherozoids 
of normal form occur. The egg, which grows without fertili¬ 
zation to form the embryo, has the double or diploid chromo¬ 
some number and on this account Farmer and Digby do not re¬ 
gard it as the physiological equivalent of an egg. 
3. Athyrium felix^foemirta var. uncoglomeratum —Stansfield. 
The account of this form is incomplete. Apparently here, too, 
there is apospory and parthenogenesis. The chromosome num¬ 
ber is about one hundred. 
4. Scolopendrium vulgare var. crispum Drummcmdae is 
aposporous and parthenogenetic. The counts of chromosomes 
varied. In the prothallium there were seventy, in the embryo 
eighty to a hundred. In the normal Scolopendrium vulgare 
