STEERE: BRYOLOGY 269 



lands. In 1929 Frans Verdoorn established Annales Bryologici, a yearbook of 

 exceptionally high quality, published for twelve years, with four supplementary 

 volumes. In 1947 W. Meijer began the publication of an interesting mimeo- 

 graphed journal Buxbaumia, for the communications of the Bryologische Werk- 

 groep of the Netherlands Natural History Society. In Japan, S. Ilattori estab- 

 lished the Journal of the Hattori Botanical Laboratory in 1947, and the several 

 small volumes published to date seem to deal almost exclusively with bryology. 

 The journals just described contain a large proportion of the original litera- 

 ture of bryology and provide access to most of the remainder, through reviews, 

 lists of publications, and the bibliographies of individual original contributions. 



Floristic Studies 



As already indicated, the past century stands out as one of unparalleled 

 botanical exploration, which resulted in bryological collections from nearly every 

 part of the world and made possible an understanding of the larger outlines of 

 bryogeography. Nevertheless, a very large amount of local and regional work 

 still remains to be done in many areas, in order to clarify and formulate floristic 

 and distributional problems. Of several bryologists studying the new and excit- 

 ing floras of the world during the past century, Carl Miiller was by far the 

 most industrious and prolific in the creation of new species and genera of mosses. 

 Perhaps half of the species of Musci described during the first fifty years of 

 the past century bear the authorship of Miiller, who, because of the reputation 

 in exotic bryology established through his great work Synopsis Muscorum (1848- 

 1851), received almost all collections made by the numerous German official 

 expeditions and private collectors of his time. Furthermore, he held a very nar- 

 row specific and generic concept (Fleischer, 1922). Miiller 's last book, published 

 posthumously (C. Miiller, 1901), contains a complete bibliography of his impor- 

 tant contributions. In the systematic and floristic study of hepatics, Franz Ste- 

 phani (cf. Beauverd, 1928) appeared as the nearly exact counterpart of Miiller 

 in his willingness to study all exotic hepatics, in the number of new species pro- 

 posed, in his narrow specific concept (cf. Verdoorn, 1934, p. 2), and, above all, 

 in his preparation of a comprehensive treatment of all the Hepaticae of the 

 world, the Species Hepaticarum (1898-1924). 



Although the number of species of bryophytes known today may be estimated 

 only with the greatest difficulty, because of the lack of any recent census, it is 

 reasonably safe to suggest that, as of 1951, the world's known flora contains 

 some 25,000 described species of Musci (Jaeger and Sauerbeck, 1870-1880; Paris, 

 1903-1906; Brotherus, 1901-1909, 1924-1925), nearly 350 species of Spliagyium 

 (Warnstorf, 1911; Paul, 1924) and perhaps 10,000 species of hepatics (Schiff- 

 ner, 1893-1895; Stephani, 1898-1924). Of course, the warning must be inter- 

 jected hastily that the numbers just quoted refer to species described, but with 

 no guarantee that they actually exist in nature, since, just as in other groups 

 of organisms, too many species ha\'e been proposed as new several times, under 

 different names, or else created in the first place on insufficient grounds (cf. 

 Fleischer, 1922; Andrews, 1951; Verdoorn, 1934, p. 2), indicating that at least 

 some of the figures cited may eventually have to be scaled downward. 



It seems appropriate to devote some space to a brief account of the progress 



