SUMMARY OF CURRENT RESEARI HES RELATING TO 



E. S. Reynolds* publishes notes on species of Botrychium from 

 Tennessee, and includes a description of a peculiar teratologic^,] specimen 

 of B. obliquum, a species which is rare in Tennessee. B. riniixianum is 

 more common. 



Bryophyta. 

 (By A. Gepp.) 



Inter-relationships of the Bryophyta.f — F. Cavers continues his 

 studies of the inter-relationships of the Bryophyta. Chapter AT. treats 

 of the morphology, anatomy, reproduction, and development of the 

 Sphagnales. and is followed by a list of sixty-two papers which heal' 

 upon the subject. Chapter VII. gives a similar, but briefer, account of 

 the Andreaeales. In Chapter VIII. the Bryales are contrasted with the 

 .Sphagnales and the Andreseales on their sporophyte characters : and the 

 classification of the Bryales is discussed from the point of view of the 

 development of the peristome. There are four sharply-marked types of 

 peristome, which permit the Bryales to be separated into the four 

 following independent groups : Tetraphidales, Polytrichales, Buxbaumi- 

 ales, Eu-Bryales. The latter group is divided into Haplolepideee, Hetero- 

 lepidese, and Diplolepideaj ; and these again are sub-divided into cohorts. 

 In Chaper IX. are discussed the inter-relationships of the higher Bryo- 

 phyta enumerated above ; and the author's views as to their phylogeny 

 are expressed diagrammatically in a pedigree table. Also an ingenious 

 argument is developed that there probably is a definite correlation 

 between the form of the archesporium and the sterile apical portion of 

 the sporogonium. Where the archesporium is dome-shaped, the sterile 

 apical tissue is practically cut off from the stream of food-material 

 passing up through the seta and columella, the nutritive material 

 becoming almost entirely used up by the developing spores. In the 

 higher mosses the archesporium is almost cylindrical, and is open above 

 and below, allowing ready passage of nutritive material to the apex of 

 the capsule, and permitting of considerable growth in that region ; thus 

 arise annulus, operculum, and peristome. Chapter X. contains a classi- 

 fication of the Bryophyta in ten orders, with their families. It contains 

 also a discussion of the old-established primary division of the Bryophyta 

 into two classes, Hepatic^ and Musci, and of the question whether the 

 Anthocerotales ought not to be excluded from the Hepaticre, and the 

 Sphagnales to be excluded from the Musci. 



In Chapter XI. the author points out that he has assumed, as a 

 working hypothesis, that the Bryophyta in the outlined scheme of classi- 

 fication form an ascending series, in which the sporogonium represents 

 an interpolated generation arising from the segmented oospore, and is 

 characterized by a gradually increasing sterilization of potentially sporo- 

 genous tissue. In Riccia is found the most primitive stage, the steriliza- 

 tion being confined to the formation of a unilamellate capsular wall. 

 Further, lie discusses} GoebeFs view as to the Marchantiales constituting 

 a descending series of reduction forms, and finds it but partially accept 



* Rhodora, xiii. (1911) pp. 14-15. 

 t New Phytologist, x. (1911) pp. 1-46. J Tom. cit., pp. 84-6. 



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