ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
627 
B. CRYPTOGAMIA. 
Cryptogamia Vascularia. 
Phytogeny of Ferns.* * * § — Returning to the subject of the relative 
antiquity of the leptosporangiate and eusporangiate ferns, Prof. F. 0. 
Bower now abandons his previous view, and adopts rather that of 
Campbell. f He discusses the points which have been relied on as 
showing an affinity between the Hymenophyllaceae and Mosses, viz. : — 
The filmy character of the leaf, the filamentous prothallium, the pro- 
jecting sexual organs, the presence of a single well-defined apical cell, 
and the reputed absence of roots in some filmy ferns ; and shows that 
none of them can be regarded as trustworthy evidence of genetic affinity. 
On the other hand, the fact that the leptosporangiate ferns are the only 
known leptosporangiate Vascular Cryptogams is some indication of their 
later origin, a view strongly supported by the facts of palseophytology ; 
the Marattiaceae attained a great preponderance in the Carboniferous 
period compared to their frequency at the present time. 
Prof. Bower is disposed to trace an affinity between the eusporangiate 
ferns and the Hepaticae, the sporophyte of the fern corresponding to the 
sporogone of the liverwort, and the isolated archesporial cells of the 
former to the united archespore of the latter. The Cycadeae have 
probably sprung from some forms allied to our modern Marattiaceae and 
Ophioglossaceae, the Coniferae from some forms allied to Lycopodiaceae. 
Apical Growth of the Prothallium of Ferns. J — Prof. D. H. Campbell 
describes the mode of growth of the prothallium of Onoclea sensibilis , 
0. Struthiojpteris, Osmunda cinnamomea, and some Polypodiaceae, and 
points out its identity, in all essential features, with that of the Hepa- 
ticae, especially in Metzgeria, Aneura, and the Anthoceroteae, as well as in 
the Marchantiaceae and Ricciaceae. This consists essentially in growth 
from a single two-sided apical cell, from the sides of which two rows of 
segments are cut off by parallel walls. From these facts he argues the 
genetic derivation of Filices from Hepaticae, the Osmundaceae and 
Marattiaceae being probably the primitive forms of the former. 
Muscinese. 
British Mosses. § — Rev. H. G. Jameson publishes a complete key for 
determining British mosses ; the first part giving the distinguishing 
characters of the genera, the second part the distinguishing characters 
of the species in all those genera which include more than a single 
British species. 
Apical Growth of Hepaticae. || — From observations on several species 
of thalloid Hepaticae, especially Marchantia polymorpha, Mr. D. M. Mottier 
has come to the conclusion that the apical growth takes place not, as 
usually supposed, from several, but originally from a single apical cell. 
* Ann. of Bot., v. (1891) pp. 109-31 (1 pi.). Cf. this Journal, 1890, p. 66. 
f Cf. this Journal, 1890, p. 637. 
+ Bull. Torrey Bot. Club, xviii. (1891) pp. 73-80 (1 pi.). 
§ Journ. of Bot., xxix. (1891) pp. 33-45, 132-42, 196-206 (1 pi.). 
|| Bot. Gazette, xvi. (1891) pp. 141-3 (1 pi.). Cf. supra, Prof. Campbell. 
