ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 459 



CRYPTOGAMS. 

 Pteridophyta. 



Vegetative Propagation in Angiopteris evecta.* — M. Eaciborski 

 describes a very effective method of vegetative propagation in this 

 Marattiaceous fern. The leaves, as in other members of the order, are 

 differentiated into leaf-base and upper leaf. The former forms a cushion 

 rhombic in section, reaching 2 dcm. in length and. bearing on its flanks 

 the fleshy lobes of the stipules. The upper leaf, consisting of leaf-stalk 

 and blade, usually lives for 2-3 years, and then withers and falls after a 

 separating cork layer has been developed between it and the leaf-base. 

 The old leaf-stalks remain many years, ten or more, on the stock. They 

 are covered with a thick brown layer ; the stipules slowly perish, while 

 the internal parenchymatous tissue functions as a water reservoir, and 

 contains the numerous gum or mucilage passages characteristic of 

 Marattiaceae. Ultimately the leaf-cushion becomes separated from the 

 stem. These separated leaf-cushions, often partially decomposed, are 

 found in considerable quantities rolled about on the steep slopes of the 

 wooded volcanic mountains in Java. They bear strong adventitious buds 

 on their flanks which rapidly take root and thus form an efficacious 

 means of plant distribution. 



Spore-casting Mechanism of Selaginella Sporangia.f — C. Stein- 

 brinck, following Goebel's work, has investigated the structural details 

 associated with the opening of the macro- and micro-sporangia and the 

 ejection of the spores. Goebel suggested that the mechanism was sup- 

 plied either by a shrinking or was of the nature of a cohesion mechanism. 

 The author finds that a cohesion mechanism is not only a plausible 

 explanation, but also the only one possible. 



Mosses. 



Irish Mosses. ! — J. Hunter publishes a large annotated list of the 

 mosses gathered by him in the neighbourhood of Londonderry and 

 Lough Swilly. Some of the localities in this region appear to be 

 particularly adapted for a rich growth of these plants. 



E. Armitage § gives a list of 107 mosses collected in July and 

 August of last year in the northern part of County Limerick. 



British Moss-Flora. || — E. Braithwaite publishes part xxi. of his 

 moss-flora, of which only two more parts remain to be issued. He 

 figures thirty species, and describes some thirty-four species in the text. 

 The genera included are Helicodontium and Habrodon of the subfamily 

 Hypnese, and nine others belonging to the subfamily Stereodonteae, viz. 

 Myurella, Heterocladium, Hylocomium, Campylium, Ctenidium, Hyocomium, 

 Ptilium, Sematophyllum, and Stereodon. 



Notes on American Hepaticae.f — M. A. Howe contributes critical 

 notes on several North American hepatics. Cephalozia connivens has 



* Bull. Internat. Acad. Sci. Cracovie, 1902, pp. 48-51. 

 t Ber. Deutsch. Bot. Ges., xx. (1902) pp. 117-28 (3 figs.). 

 X Journ. Bot., xl. (1902) pp. 191-6. § Tom. cit., pp. 226-8. 



|| R. Braithwaite, The British Moss-Florn, part xxi. April 1902, pp. 129-68 

 (pis. cix.-cxiv.). If Bull. Torr. Bot. Club, xxix. (1902) pp. 281-9. • 



2 H 2 



