Developments of the Oophyte in Trichomanes . 301 
De Bary as apogamy, or loss of sexual function ; only in the 
case above described the sexual organs are not arrested or 
lost, but the whole sexual generation.’ In view of the fact 
that till the present time no example of coincidence of 
apospory and apogamy in the same species and individual has 
been described, this conclusion above quoted was a bold one ; 
and even now in TV. alatum the case is not exactly parallel. 
Here the sexual generation is not arrested ; it is present and 
of considerable size, even the sexual organs are not entirely 
aborted, for, though no archegonia have been found, 
antheridia are far from rare. But notwithstanding that 
TV. alatum is a much clearer case of the coincidence of 
apogamy and apospory in the same individual than the case 
of Isoetes , its discovery will lend justification to the view 
expressed by Goebel, — a view which was previously based on 
less substantial grounds. 
Apogamy is known to occur in the following Ferns : — * 
Pteris cretica, in which it was first described by Farlow 1 , 
and again by De Bary 2 in Aspidium Filix-mas , var. cristatum , 
Aspidium falcatum , and Todea africana 3 . These Ferns 
present the phenomenon in different degrees of complete- 
ness ; though all bear more or less numerous antheridia 
(which at least in some cases produce mature spermato- 
zoids 4 ), archegonia are apparently altogether absent in 
Aspidium Filix-mas , var. cristatum , in Pteris cretica they 
are never fully developed, but in Aspidium falcatum and 
Todea africana they apparently attain maturity. Thus, of 
the Ferns above-named, the most complete type of apogamy 
is that shown in Aspidium Filix-mas , var. cristatum , in which 
archegonia are entirely absent, and the antheridia few ; as 
to the actual formation of mature spermatozoids in this 
species I find no definite statement 5 . In the case of TV. 
alatum the apogamy is quite as complete as, and apparently 
1 Q. J. M. S. Vol. xiv. p. 267. 2 Bot. Zeit. 1878. 
3 Sadebeck, in Schenk’s Handbuch, Yol. i. p. 233, &c. 
4 De Bary, 1 . c. p. 459. 5 De Bary, 1 . c. p. 470. 
Y 2 
