ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 495 



describes an annulus which he considers to be the peripheral portion of 

 the upper side of the spore-sac. It is below the epiphragm, at about 

 the level of the sporogonium-mouth. Between the epiphragm and this 

 annulus there is formed a hollow, through the resorption of the cell- 

 tissue. The author surmises that this hollow space contains air, which 

 plays a part in the throwing off of the lid. The annulus does not occur 

 in Polgtrichum alpinum, since in this species the epiphragm rests on the 

 sporogonium-mouth. The author describes also in detail the manner in 

 which the epiphragm is connected with the peristome-teeth. He finds 

 that P. alpinum, P. gracile, and P. sexangulare, differ from the other 

 species of the family in having the epiphragm toothed at the margin, 

 and situated below the tips of the peristome-teeth. Catharmeea 

 undulata is, according to the author's experience, always dioicous, and 

 the male plants are very rare. The plentiful fertility of the species is 

 difficult to explain. C. HaussJcnechtii is distinguished from (J. undulata 

 both by its synoicous inflorescence and by the epidermis cells of the 

 sporogonium. In C. Raussknechtii they are 2-4 times longer than broad ; 

 in G. undulata they are hardly so long as, or very slightly longer than, 

 broad. In treating of the genus Polytrichum, the author writes of the 

 limiting of the mid-rib, which he considers is formed by the one-layered 

 border of the lamina. This is shown particularly on the under side of 

 the leaves of P. juniperinum, P. strictum, P. piliferum, and P. htjper- 

 boreum, in which one finds inside the one-layered border a zone of quite 

 different epidermis cells. These four species, on the strength of this and 

 other characters (entire leaves with recurved margin, and rounded or 

 conical marginal cells of the leaf lamellae), form a special group of 

 the genus. The sporogonium annulus is very poorly developed in 

 Pohjtrichum, though it is present in all the species. The principal part 

 of this paper is written in Norwegian, but portions of more general 

 interest are in French. 



Drepanocladus.*— J. Ambroz publishes the results of a study of 

 the Bohemian species of the very difficult and variable genus Drepano- 

 cladus, founded on the abundant material collected by Velenovsky and 

 himself. After giving a detailed historical survey, he furnishes a key 

 for the determination of the thirteen species, and sub-species, etc., found 

 in the district. These he arranges in five groups, some of which are 

 new. 



Vegetative Reproduction of Sphagnum.f — E. Melin publishes the 

 first of a series of studies on the biology of Sphagnum. In it he 

 discusses the vegetative reproduction, which hitherto has only been 

 observed in specimens under culture. The author here describes the 

 process in S. compactum, 8. tenellum, and S. Lindhcrgii, observed under 

 natural conditions. Innovation -shoots were plentifully developed from 

 both the apical and lateral short branches, and bore no protonemal 

 filaments at their base. 



* SB. kgl. bohm. Ges. Prag. Math.-Nat. Kl., v. (1914) pp. 1-66 (figs.). See also 

 Bot. Centralbl., cxxviii. (1915) pp. 379. 



t Svensk. Bot. Tidskr., viii. (1914) pp. 191-200 (figs, in text). See also Bot. 

 Centralbl., cxxviii. (1915) p. 166. 



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