404 SUMMARY OF CURRENT RESEARCHES RELATING TO 



the United States. The name Herherta Gray is preferable to Schisma 

 Dmn. and Sendtnera Endl. The morphological features of the genus 

 are well marked ; and the structure of the rhizome, secondary stems, 

 leaves, underleaves, and vittas, and the cells and cell-walls, are described 

 in detail. The cells of the vittfe have peculiar thickening bands on 

 their walls, which Ijecome obvious when treated with suitable reagents. 

 The male and female inflorescences and the structure of the capsule- wall 

 are described. After a careful study of the European and North 

 American representatives of the genus, Evans has come to the conclusion 

 that they should be grouped in four species : — 1. H. adnnca, found in 

 Scotland, Wales, Norway, Faroe Islands. 2. H. Sendtneri, confined to 

 Austria and Germany. 3. H. Hukhinxiae^ a new species occurring in the 

 British Isles, Norway, N.W. America. 4. H. tennis, a new species spread 

 over the eastern United States. There has been much confusion and 

 misunderstanding in ihe past, which is cleared up by Evans's descriptions, 

 figures and key. 



Eiccia in North America.* — M. k. Howe gives a resume of the 

 history of Riccia Beijrichiana Hampe (1838), originally discovered in 

 Georgia and not found again until lOl-t, when Howe made a special 

 search for it. The new material suggested that the species is not 

 entirely distinct from R. Lesciiriana Austin (1869), a species widely 

 distributed in the United States. And a careful investigation of much 

 living material of both species has revealed that in spite of erroneous 

 statements as to size of thallus and spores, presence or absence of 

 marginal cilia, the two species are one and the same — a conclusion 

 which is confirmed by the spore-sculpture. Some of the European 

 material referred to R. Lesciiriana belongs to it, but non-ciliate 

 European material seems to be more closely related to R. f/hmca or 

 R. bifurca. The author also describes the structure of R. McAllister i. a 

 new species from Texas ; and adds some notes on the structure of 

 R. violacea Howe, and the distribution of that species in the West 

 Indian islands. 



Plagiothecium.f — A. Yasuda describes and figures the structure of 

 a new Japanese moss, Plagiothp.cium azumense, which is allied to the 

 European F. necJceroideum, but differs in the shape of its leaves, in its 

 laxer areolation, and in the absence of flagelliform branches. 



Synopsis of European Sphagna. t — J. A. Wheldou pubhshes a 

 Synopsis of the European Sphagna, indicating the species, varieties and 

 forms occurring in the British Isles, with brief descriptions of many of 

 the forms. It is compiled from Warnstorf's " Sphagnologia Universalis " 

 (1911), with additions, and includes fifth-nine species and innumerable 

 varieties and forms, mostly defined with brief diagnoses. Brief key 

 characters are also given in some of the groups, especially in the Cuspi- 

 data and Subsecunda. To some extent this synopsis is supplementary 



* Bryologist, xx. (1917) pp. 33-6 (1 pi). 



t Tokyo Bot. Mag., xxx. (1916) pp. 89-91 (figs.) 



t Synopsis of the European Sphagna. Darwen : W. H. Western (1917) 42 pp. 



