270 A CENTURY Of PROGRESS IN THE NATURAL SCIENCES 



made in floristic studies of the world's biyophytes, especially since no survey 

 of this sort has appeared for twenty years. Europeans initiated the study of 

 bryophytes, and Europe continues to be the center for research in bryology, in 

 spite of increasing activity in this field in other parts of the world, especially 

 in the United States. Consequently, the bryophytes of Europe are by far the 

 best known, and the publications concerning them seem to be almost innum- 

 erable. In 1853, one of the most important bryological floras ever published, 

 which still sets a high standard both for illustration and for descriptions, neared 

 completion. This work, the Bryologia Europaea (Bruch, Schimper and Giimbel, 

 1836-1855) appeared at irregular intervals in fascicles of varying numbers of 

 pages over a period of nearly twenty years (Barnhart, 1944). Since the com- 

 pletion of the Bryologia Europaea many further important pul)lications cover- 

 ing the bryophytes of Europe have appeared, of which especial mention should 

 be made of the valuable contributions of Limpricht (1885-1903) and of Monke- 

 meyer (1927) on the mosses, and of K. Mtiller (1905-1916, 1951) on the he- 

 patics, in Rabenhorst s Kryptogamen-Flora von Deutschland, Osterreich und der 

 Schweiz. The works of Roth (1904-1905) and Schiffner (1901-1937) also de- 

 serve mention. 



The bryophyte flora of almost every individual European country has been 

 treated fully, and sometimes repeatedly, by substantial publications. Examples 

 of outstanding contributions for different countries are : for Great Britain, those 

 by Braithwaite (1880-1905), Pearson (1902), Dixon (1924), Macvicar (1926), 

 and Sherrin (1927); for Spain and Portugal, by Casares-Gil (1919-1932), Frei- 

 tas (1948), Allorge (1947), and Cortes Latorre (1951) ; for Italy, by De Notaris 

 (1869), Zodda (1934), and Giacomini (1947); for France, by Husnot (1884- 

 1890, 1922); for Belgium, by Demaret (1945), and Vanden Berghen and Duvi- 

 gneau (1943) ; for Germany, by many authors, including several excellent provin- 

 cial floras (cf. Monkemeyer, 1927); for the east Baltic area, by Malta (1931); 

 for Denmark, by Jensen (1915, 1923); for Sweden, by Moller (1911-1936); for 

 Norway, by J0rgensen (1934) ; for Scandinavia as a whole, by Brotherus (1923), 

 Arnell (1928), and Jensen (1939); for Austria, by Juratzka (1882), and Gams 

 (1950); for Switzerland, by Amann (1912), and Meylan (1924); for Czechoslo- 

 vakia by Pilous (1948) ; for Slovakia by Smarda (1948) ; for Dalmatia by Latzel 

 (1931), and K. Miiller (1948b) ; and for Russia by Warnstorf (1912-1913), Sa- 

 vicz (1936b), Savicz and Ladyzhenskaja (1936), and Lazarenko (1951). 



The study of bryology in North America remained much neglected during 

 the first half of the last century, in spite of the great activity shown in Europe. 

 The excellent early works that did appear are consequently all the more impor- 

 tant, and among them should be cited those of Sullivant (1856, 1864, 1874), 

 Lesquereux and James (1884), and Macoun and Kindberg (1892, 1902). Dur- 

 ing the past fifty years, however, the study of bryophytes developed rapidly in 

 North America, and many important floristic studies have been published, cul- 

 minating in the monumental works of Grout (1928-1940) on Musci and of Frye 

 and Clark (1937-1947) on Ilepaticae, which cover all of North America north 

 of Mexico. Other bryological works of more restricted geographical application 

 cover the eastern United States (Grout, 1903-1908; Dunham, 1951), the north- 

 western United States (Clark and Frye, 1928; Jones, 1930), Alaska (Cardot and 

 Theriot, 1902; Persson, 1952), California (Howe, 1899), Connecticut (Evans and 



