148 
bestimmte Lebensbedingungen (die meisten H. sind Bewohner feucht- 
warmer Tropengebiete) im Zusammenhange steht“. (p. 336.) 
Weiter geht Wettstein nicht. Wohl aber Bower und Lotsy. 
3. Bowers System.?,',"°) x 
In „Hookers Lecture 1917“ (p. 116) bespricht Bo wer alle Merk- 
male, die die Phylogenie der Farne beriicksichtigen sollte. Es sind das: 
(I—XIIL.) External form, Cellular segmentation, Dermal appendages, 
Stelar structure, Leaf-trace, Venation, Soral position, Soral construc- 
tion, Indusial protections, Sporangial structure, Mechanism of dehis- 
cence, Spore-output, Character of spore. XIV. Form of prothallus: 
relatively massive in primitive types, relatively delicate in derivative 
types. But the character is unrealiable. XV. Sexual organs: sunken 
in primitive types, projectinc in derivative types. XVI. Number of 
spermatocytes in each antheridium: large in primitive types, smaller 
in derivative types. XVII. Embryology. 
Bei der Besprechung des phylogenetischen Entwickelungsganges 
des Gametophyten macht er auf die immer stärkere Reduktion auf- 
merksam. An die massiven Prothallien der Lycopodiaceen, Ophio- 
glossaceen und Marattiaceen schliessen sich die Osmundaceen an. 
„These facts strongly suggest that the Fern-phylum has undergone a 
progressive simplification of the prothallus, and indicate an origin 
like the rest from a massiv source“) (p. 710). 
Es werden die Farne eingeteilt (p. 496). „According to the ar- 
rangement and succession of development of their sporangia the 
homosporous Ferns have been divided into three series: the Sim- 
plices, in which the sporangia of a sorus are produced simultane- 
ously: the Gradate, in which there is a definite succession in time 
and space in their production: and the Mixtae in which there is a 
succession in time but non regular succession in space“. 
Auch die Stellung der Sori ist sehr wichtig :'") (p. 470). „That 
from a very early period the Leptosporangiate Ferns have progressed 
a long two paralell lines, the one characterized by a marginal, the 
other by a superficial position of the spore-bearing organs; and 
that these lines have remained phyletically distinct throughout.“ 
So werden die Farne eingeteilt:!°) (p. 471) und?) (p. 498). 
Marginales : Superficiales 
Botryopterides Marattiaceae 
Simplices Ophioglossaceae Gleicheniaceae 
Schizaeaceae g. Todea 
g. Osmunda 
Loxsomaceae Cyatheaceae 
Gradatae Hymenophyllaceae Woodsieae 
Dicksonieae Onocleinae 
Thyrsopterideae 
Davallieae Aspidieae 
Oleandeae Blechniinae 
Mixtae : Aspleninae 
Pterideae.**) 
**) Nach späteren Untersuchungen") sollen die Pterideae von den Margi- 
nalen abgeleitet werden. 
