]N GENERAL 



159 



this work necessarily contains many imperfections and cannot be 

 considered in any sense as a revision, as too many have regarded 

 it, it has made accessible to workers throughout the world the 

 greater part of the technical descriptive literature of the subject 

 and has made possible the recent extensive advances in the defi- 

 nite knowledge of species.* 



The other work is that of Brefeld, which is of an entirely dif- 

 ferent character. His studies have chiefly appeared in the twelve 

 quarto heften, Botanische Untersuchungen iiber Schimmelpilze, 

 I. -IV. 1872-1881 ; Botanische Untersuchungen iiber Hefenpilze, 

 V. 1883 ; Untersuchungen aus dem Gesammtgebiete der My- 

 kologie, VI. -XII. 1 884-1 897, and involve a most elaborate ac- 

 count of the development of fungi from artificial cultures and 

 the study of their comparative morphology. While many new 

 lines of relationship have thus been worked out, Brefeld' s sweep- 

 ing conclusions regarding the origin of the higher fungi from the 

 lower are not being borne out by the work of other investigators, 

 and we are still in the dark in regard to the origin of the higher 

 and more specialized groups. f 



A valuable summary of our knowledge of the physiology of 

 the fungi, tho not including the most recent additions, may be 

 found in Zopf, Die Pilze.\ Lud wig's Lehrbuch der niederen 

 Kryptogamen (1892), andTubeuf and Smith's Diseases of Plants 

 induced by Cryptogamic Parasites (1897), are valuable for stu- 

 dents of plant diseases, as are the more elaborate treatises of 

 Soraurer § and Frank. || A valuable series of fungi exsiccati 

 parasitic on cultivated plants has been issued by Seymour and 

 Earle under the title Economic Fungi ; eleven fascicles (550 

 species) have appeared already. 



* Three annual supplements to the Sylloge have appeared as Beibiatter 

 to Hedwigia, 1896, 1897 and 1898, giving a classified index to species of 

 fungi described during the preceding years as follows : 1895 — 1252 species ; 

 1S96 — 1313 species ; 1897 — 1476 species. Surely the end is not yet ! 



■}- A somewhat compact summary of Brefeld' s system has been made by 

 his assistant, Von Tafel. Vergleichende Morphologie der Pilze, Jena, 1892. 



X In Schenk, Handbuch der Botanik, 4 : 271-781. 1890. Also sepa- 

 rately paged. 



I Soraurer. Handbuch der Pflanzenkrankheiten. Zweite Auflage. 2 

 vols. Berlin, 1886. 



II Frank. Die Krankheiten der Pflanzen. Zweite Auflage. 3 vcls- 

 Breslau, 1895. 



