CHAP.V.] the Influence of the Knowledge of Cryptogams. 205 



volumes and the figures large folios ; the abundance of forms 

 in the Thallophytes proved to be so great that many botanists 

 devoted their whole attention to them, many collected and 

 described only the Algae, others only the Fungi and Lichens. 

 It is true that a deeper insight into the connection of these 

 forms of life with one another and with other plants was not to 

 be obtained in this way ; still an empirical basis was formed 

 for a knowledge of the Cryptogams, such as had been estab- 

 lished for the Phanerogams by the herbals of the iyth century. 

 All forms open to observation were named and arranged in one 

 way or another ; and there was no difficulty in understanding 

 what form was meant, when names, or tables and figures, were 

 cited from the various books. Of such works, those of 

 Agardh 1 , Harvey, and Kiitzing on the Algae, those of Nees 

 von Esenbeck 2 , Elias Fries, Leveille, and Berkeley on the 

 Fungi, and especially Corda's elaborate work on the latter 

 plants are the most valuable. 



1 Karl Adolf Agardh (1785-1859) was until 1835 Professor in Lund, 

 afterwards Bishop of Wermland and Dalsland. Jacob Georg Agardh, born 

 in 1813, was Professor in Lund. William Henry Harvey (1811-1866) was 

 Professor of Botany in Dublin. Friedrich Traugott Kiitzing, bom in 1807, 

 was Professor in the Polytechnic School of Nordhausen. 



a C. G. Nees von Esenbeck published his 'System der Pilze und 

 Schwamme' in i8i6j Th. F. L. Nees von Esenbeck, in conjunction with 

 A. Henty, a ' System der Pilze ' in 1837. The first (1776-1858) was for a 

 long time President of the Leopoldina, Professor of Botany in Breslau, and 

 one of the chief representatives of the nature-philosophy. Elias Fries, born 

 in 1794, became Professor of Botany in Upsala in 1835 ; he died in 1878. 

 Leveille (1796-1870) was a physician in Paris. August Joseph Corda was 

 born at Reichenberg in Bohemia in 1809, and became custodian of the 

 National Museum in Prague in 1835; b- e undertook a journey to Texas in 

 1848, from which he never returned, having probably perished by shipwreck 

 in 1849. \Veitenweber, in the ' Abhandlungen der Bohmischtn GeselU 

 schaft der Wissenschaft,' Bd. 7, Prag, 1852, gives a full account of this 

 eminent inycologist. Corda was the first who thoroughly applied the micro- 

 scope to copying and describing every form of Fungus that was known to him, 

 and especially the minuter ones. His ' Icones Fungorum hucusque cognitorum ' 

 (1837-1854) are still an indispensable manual in the study of the subject. 



