142 HISTORY OF BOTANY 



the " antiphyte," and described the alternation of 

 generations in Thallophyta as " homologous " and that 

 in Archegoniatae as " antithetic/' It would appear 

 that he did not regard the cluster of cells formed by the 

 division of the oosperm as having any counterpart in the 

 life-cycle of the Archegoniatae, for he speaks of Algae as 

 having three generations. 



In 1868 Sachs published his famous textbook, the 

 first really important general statement on botany as a 

 whole since Schleiden's Gmndzuge in 1842. Subsequent 

 editions were published in rapid succession, and an 

 English version appeared in 1882, based on the fourth 

 German edition of 1874. In this work Sachs upheld the 

 views of Celakowski, and founded a group of Thallophyta 

 called Carposporeae, which included Ascomycetes and 

 Rhodophyceae, in all of which he recognised an alternation 

 between a sexual generation and a parasitic sporocarp. 

 He defined the word " spore " as a reproductive cell 

 resulting directly or indirectly from an act of fertilisation, 

 with or without the intervention of a vegetative phase 

 " all other unicellular and nonsexual organs of repro- 

 duction we shall not term ' spores ' but gonidia or conidia." 

 Sachs added ;_" If the act of fertilisation does not result 

 in the production of any vegetative structure, or the 

 second generation be altogether suppressed, the fertilised 

 oosperm would then become a spore ... an equivalent 

 for the whole of the second generation." This is of 

 course a somewhat pedantic subordination of the facts 

 to the exigencies of a terminology. The fusion of an 

 ovum and a sperm results in the formation of an oosperm 

 and an oosperm only. If the terminology be defective 

 that does not alter the fact. In lumping together Algae 

 and Fungi that exhibit this carposporic habit Sachs is 

 reviving the old error of classifying on one " predeter- 

 mined mark " which had hampered phylogenetic taxo- 

 nomy since the days of Caesalpino. 



In 1874 Farlow, an American botanist, made the 



