Developments of the Oophyte in Trichomanes. 289 
these are examples of apogamy, the sexual process being 
entirely eliminated. 
Conclusion. 
Of the observations above detailed we shall do well to keep 
distinct from one another those which relate to normal pro- 
cesses, and those which may be regarded as abnormal ; to 
the former category belong the observations on the conform- 
ation of the oophyte, on the antheridia and archegonia, and 
(perhaps) on the reproduction by gemmae and by sporophytic 
budding ; these will have their comparative value ; to the 
latter belong the observations on apospory and apogamy, 
which have rather a teratological, and generally physiological 
interest. The former will be first considered. 
Goebel has recently given 1 , in a tentative way it is true, 
a sketch of the possible phylogenetic development of the 
Hymenophyllaceae, based on the characters of the oophyte. 
He suggests that the phyl ©genetically oldest form of the 
oophyte was the branched cellular filament, on which the 
sexual organs were directly inserted, and notes that this form 
is still to be seen in many species of Trichomanes [e.g. our 
T r. pyxidiferuin\, but with the archegonia inserted on a multi- 
cellular receptacle : this receptacle is in the present paper 
termed the archegoniophore. He regards as the next step 
the widening out of branches of the filamentous protonema 
into flattened expansions [as in Tr. incisum and Tr. smuosum , 
described by Mettenius, and in our Tr. alatum\ ; on these 
flattened expansions the sexual organs are inserted in Tr. 
incisum and Tr. sinuosum. He suggests it as possible that 
these may have been first formed as expansions of the simpler 
archegoniophores, and that they ultimately became developed 
in point of time before the appearance of the archegonia, and 
he supports this view by comparison of other Vascular Crypto- 
gams. He proceeds under his fifth head to state that 'the 
prothallus of Hymenophyllum arose from that of Trichomanes 
1 Morphologische und Biologische Studien, in Ann. Jard. Bot. Buitenzorg, 1887. 
