A TEXTBOOK OF THEORETICAL BOTANY 

 contd. 



2136 



X. Phaeophyceae 



3. Cutleriales 



Laminariales 

 Tilopteridales 

 Dictyotales 

 Fucales 



XI. Bangiales 



XII. Rhodophyceae (Florideae) 



1. Nemalionales 



2. Gigartinales 



3. Rhodymeniales 



4- 



Ceramiales 



In 1916 West published his monograph on the Green Algae, with which 

 he included the Myxophyceae (Cyanophyceae), Peridinieae, Bacillarieae 

 (Diatomaceae) and the Chlorophyceae. West never gave a full classification 

 of the Algae as a whole, but his treatment of the Chlorophyceae has had so 

 much influence on the teaching of the group in Britain that an outline 

 of his classification may be given. It was influenced largely by the sug- 

 gestions put forward by Bohlin in 1901 and Blackman and Tansley in 1902. 



CHLOROPHYCEAE II. Akontae 



I. Isokontae i- Conjugatae 



I. Protococcales III. Stephanokontae 



Siphonales i. Oedogoniales 



Siphonocladiales IV. Heterokontae 



Ulvales I. Heterococcales 



Schizogoniales 2. Heterotrichales 



Ulotrichales 



3. Heterosiphonales 



Meanwhile in America various modifications of these systems were 

 produced, which may be said to have culminated in the proposals set out 

 by Smith in his " Cryptogamic Botany " published in 1938. Smith 

 elevates the main groups of the Algae to phylum rank and dispenses with 

 the old term Thallophyta. The following is an outline of his proposals: 



I. Chlorophyta 



a. Chlorophyceae 



1. Volvocales 



2. Tetrasporales 



3. Ulotrichales 



4. Ulvales 



5. Schizogoniales 



6. Cladophorales 



7. Oedogoniales 



8. Zygnematales 



9. Chlorococcales 



10. Siphonales 



11. Siphonocladiales 

 p. Charophyceae 



11. Euglenophyta 



1. Euglenales 



2. Colaciales 



I 



