520 ßryophyten. 



in successive chapters of the Sphagnales and Andveaeales and passes 

 on to the Bvyales, the Classification of which he discusses from the 

 point of view of the peristome. Sharply marked types of peristome 

 permit the Bryales to be seperated into the four following groups: 

 Tetvaphidales, Polytvichales, Buxbaiimiales, Eu-Bryales. The last- 

 mentioned group is divided into Haplolepideae, Heterolepideae, and 

 Diplolepideae ; and these again are sub-divided into cohorts. The 

 Inter-relationships of the higher Bvyophyta are discussed and are 

 diagrammatically represented in a pedigree table. The author puts 

 forward the argument that there probably is a definite correlation 

 between the form of the archesporium and the sterile apical portion 

 of the sporogonium. A dome-shaped archesporium practicall}' cuts 

 off the apical tissue from the stream of food-material passing up the 

 seta and columella, the nutritive matter being exhausted by the 

 developing spores. The cylindrical archesporium of the higher 

 mosses allows ready passage of food-material to the apex of the 

 capsule; hence the development of annulus, operculum and peristome. 



A Classification of the Bvyophyta in ten Orders, with their fami- 

 lies is given; and the old-etablished primary division into the tvvo 

 classes, Hepaticae and Musci, is discussed, as also the question 

 whether the Anthocevolales ought not to be excluded from the 

 Hepaticae, and the Sphagnales from the Musci. 



Finally the author points out that in his Schema of Classification 

 he has assumed as a working hypothesis that the Bvyophyta form 

 an ascending series, in which the sporogonium represents an inter- 

 polated generation arising from the segmented oospore and is cha- 

 racterized by a gradually increasing sterilization of potentially spo- 

 rogenous tissue. The most primitive stage is Riccia where the 

 sterilization is confined to the formation of a unilamellate capsular 

 wall. As to Goebel's view that the Marchantiales constitute a 

 descending series of reduction-forms, he finds it but partially accep- 

 table. If the Bvyophyta constitute an ascending group with Riccia 

 exhibiting the most primitive form of sporogonium, the conclusion 

 is natural that the Bryophyte sporogonium hat an antithetic origin, 

 and has never been anything but a sporogonium. As to theivascular 

 plants, and the Suggestion that the starting-point of the Ptevidophyta 

 may be sought in the sporogonium of Anthocevos, the great diffi- 

 culty is to explain how roots and leaves originated. It is much easier 

 to infer that the Bvyophyta and Ptevidophyta had a collateral origin. 



A. Gepp. 



Cutting, E. M., On androgynous receptacles in Mavchantia. 

 (Ann. Bot. XXIV. p. 349—357. 5 figs. 1910.) 



The author gives an account of some abnormal archegoniopho- 

 res of Mavchantia which were partially antheridiiferous. He discus- 

 ses the meaning of this, and cites instances of a simular condition 

 in other genera. A. Gepp. 



Dixon, H. N., Supplementary Note on Mosses ofPrince 

 Charles Foreland, Spitsbergen. (Trans. Proc. Bot. Soc. Edin- 

 burgh. XXIV. p. 93-94. 1910.) 

 A list of eight species, three of which are supplementary to 

 those enumerated by Dr. Hagen (op. cit. XXIII. p. 326. 1908) as 

 having been collected by Dr. Bruce's expedition of 1906—7. 



A. Gepp. 



