2134 A TEXTBOOK OF THEORETICAL BOTANY 1 



been known of the internal structure and methods of reproduction to make 

 an attempt at a natural arrangement possible. The first important contribu- 

 tion to the subject was the publication by Dawson Turner (1808-19) o^ 

 " The Fuci ", an ambitious work in four volumes, containing coloured ^ 

 pictures of many species. His facts were based upon his own observations, 

 made on specimens provided for him by Robert Brown and other botanical 

 travellers, and did much to clarify the knowledge of seaweeds. In the 

 same year that Turner completed his work, Lyngbye published his 

 " Tentamen Hydrophytologiae Danicae " which was another valuable 

 contribution to algology. The first truly comprehensive treatment of the 

 Algae came from the pen of J. G. Agardh and was published serially 

 between 1848 and 1898. This monumental work, entitled " Species, 

 Genera et Ordines Algarum", did for the Algae what Persoon did for the 

 Fungi, and provided the foundation for a general knowledge of the group. 

 In 1843 Kutzing published his " Phycologia Generalis " and later in 1860-1 

 his " Tabulae Phycologicae", both of which contributed much new 

 material, especially a series of excellent figures. The classic contribution 

 of Thuret and Bornet, " Etudes Phycologiques", appeared in 1878 with 

 very fine illustrations and helped to encourage the microscopic study of the 

 reproductive organs of the Algae, and from that time the study of algology 

 became much more widely undertaken. 



The earlier study of the Algae soon revealed similarities between the 

 reproductive organs of certain genera and those of the Fungi. It is not 

 surprising therefore to find that Fungi were regarded as Algae which had 

 lost their chlorophyll. Accordingly, to each of the main groups of Algae 

 were appended certain fungal groups which it was thought had been derived 

 from them. This view was maintained for a considerable time and it was 

 not until well into the twentieth century that the separate derivation of the 

 Fungi and the Algae was generally accepted. 



The most extensive systematic work on the Algae was by de Toni, 

 whose " Sylloge Algarum " appeared in a series of volumes published 

 between 1889 and 1924. Unfortunately the phylogenetic study of Algae 

 advanced so much during this long period that the method of classification 

 was already somewhat out of date before the last volume appeared. The 

 work, however, is of great value in that it contains precise descriptions of a 

 great proportion of all the known algal species. 



The first system of classification which we must consider in detail 

 is that of Engler and Prantl in the " Natiirliche Pflanzenfamilien". 

 Since this system considers the Fungi to be at least in part derived 

 from the Algae, the classification of the two groups is to some extent 

 mixed. 



The following is therefore an outline of the classification by 

 Engler published in the " Syllabus der Pflanzenfamilien", seventh edition, 

 1912: 



