Fig. 74 Phaeostroma bertholdt. Thallus ramifying in Scytosiphon 

 showing sporangia (s) and a hair {h). (After Oltmanns.) 



minate in a typical hair. Plurilocular sporangia are produced, either 

 in series or singly, in terminal or intercalary positions. There are 

 numbers of these reduced forms and identification is impossible 

 unless the reproductive organs are present. 



REFERENCES 



General 



Fritsch, F. E. (1945). Structure and Reproduction of the Algae^ Vol. II, 

 pp. 49-60. Camb. Univ. Press. 



Ectocarpus 



Hamelj G. (1939). Bot. Notiser, p. 65. 



Knight, M. (1929). Trans. Roy. Soc. Edinb., 56, 307. 



PapenfusSj G. (1935). Bot. Gaz., 96, 421. 



Schussnig, B. and Kothbauer, E. (1934). Ost. Bot., 83, 81. 



* Sphacelariales 



The next three types belong to the Sphacelariales, an order fre- 

 quently known as the *Brenntalgen' because they possess a very 

 characteristic large apical cell with dense brown, tanniferous con- 

 tents, the detailed classification of the group being based primarily 

 upon the behaviour of this apical cell at branch formation. The 

 plants have regular branching and a bilateral symmetry, both of 



135 



