Filicales. 
29 
occur on a more or less modified ventral lobe of the frond. The 
marginal origin of the sporocarp reported by Mr. Johnson, renders 
this likeness less exact. 
To the Salviniaceae and to the Psaronieae (so far as we can 
judge from the vegetative organs of the latter with which alone we 
are acquainted) the Ophioglossacete show few indications of affinity. 
Though the Marattiacete and Ophioglossacete are usually 
grouped together as the Pilicineae Eusporangiatae, the connexion 
between them does not appear to be close. The eusporangiate 
origin and exannulate condition of the sporangia may well be 
primitive in both, but the different structure of the gametophyte 
and stele show that their ancestors must have begun to diverge 
from one another a very long time ago. 
LITERATURE QUOTED. 
1 . 
2 . 
3. 
4 . 
5 . 
6 . 
7 . 
8 . 
9 . 
10 . 
11 . 
12 . 
E. A. Newell Arber. “ On the Past History ot the Ferns.” Annals of 
Botany, 1906. 
L. A. Boodle. “ Comparative Anatomy of the Hymenophyllaceae, 
Schizzeaceze and Gleicheniaceze.” I. On the Ana¬ 
tomy of the Hymenophyllaceze.” Annals of 
Botany, 1900. 
F. O. Bower. ‘‘Studies in the Morphology of Spore-producing 
Members. I. Equisetineze and Lycopodineze.” 
Philosophical Transactions of the Royal Society of 
London, Series B, Vol. 186, 1893. 
,, Ditto. ‘‘II. The Ophioglossaceze.” Dulau & Co., 1896. 
,, Ditto. ‘‘III. The Marattiaceze.” Philosophical 
Transactions of the Royal Society of London, Series 
B, Vol. 190, 1897. 
,, Ditto. ‘‘IV. The Leptosporangiate Ferns.” Philo¬ 
sophical Transactions of the Royal Society of 
London, Series B, Vol. 196, 1899. 
,, Ditto. ‘‘V. General Comparison and Conclusion.” 
Philosophical Transactions of the Royal Society of 
London, Series B, Vol. 196, 1903. 
,, il Ophioglossum simplex." Annals of Botany, 1904. 
,, “ The Origin of a Land Flora,” 1908. 
,, “ Note on Ophioglossum simplex , Ridley.” Annals of 
Botany, 1908. 
G. Brebner. “ On the Anatomy of Dancea and other Marattiaceze.” Annals 
of Botany, 1902. 
H. Bruchmann. 11 Das Prothallium und die Sporenpflanze von Botry- 
chium lunaria." Flora, 1906. 
13. D. H. Campbell. “ Mosses and Ferns.” Second edition, 1905, 
14. ,, “ The Affinities of the Ophioglossaceze and Marsi- 
leaceze.” American Naturalist, 1904. 
15. ,, “ Studies on the Ophioglossaceze.” American 
Naturalist, 1907. 
