74 D. M. JOHN, J. H. PRICE, C. A. MAGGS & G. W. LAWSON 



validity of many characteristics previously employed taxonomically. This results in the reduction 

 of accepted species to three (Erythrotrichia boryana, E. cornea, E. welwitschii), all of which have 

 been reported for the present area. 



Erythrotrichia boryana (Mont.) Berth. 

 Canaries (6; 23). 

 Mauritanie (38). 

 Western Sahara (38). 



Note. For detailed synonymy, see Heerebout (24). Material identifiable as Erythrotrichia 

 boryana may be expected further south in the present area, since Heerebout considered Baardseth's 

 (1941) E. tristanensis synonymous with E. boryana. 



Erythrotrichia carnea (Dillw.) J. Ag. 



Ascension (unpublished). 



Benin (28; 30). 



Canaries (6; 19; 24; 29). 



Cape Verde Islands (29). 



Gabon (31). 



Gambia (33). 



Ghana (28; 29; 41 A). 



Liberia (13; 28). 



Mauritanie (38). 



Senegal (29). 



Sierra Leone (32). 



Togo (28; 30). 



[As Erythrotrichia ceramicola Aresch.] 



Cape Verde Islands (5). 



[As Erythrotrichia ceramicola (Lyngb.) Aresch.] 



Cape Verde Islands (5). 



[As Erythrotrichia investiens (Zanard.) Bornet] 



Canaries (6; 18; 19). 



Sierra Leone (3). 



'. . . Atlantique nord (de 1'Angleterre aux Canaries.' (18). 



[As Erythrotrichia kylinii Gardn.] 



Senegal (12). 



Note. Dangeard (12) had some doubt about the identity of the Senegal specimens. He stated 

 that they resembled Erythrotrichia bertholdii, except that they possessed 2-3 basal cells forming 

 a rudimentary disc, and were very similar to E. californica Kylin ( = E. tetraseriata Gardn.). 

 However, all three names were considered by Heerebout (24) to be synonyms of E. carnea. 



[As Erythrotrichia obscura Berth.] 

 Canaries (6; 11; 19; 23; 41). 



Note. Heerebout (24) indicated that the early stages of development of '". bertholdii' were 

 always monosiphonous, with sporulation in polysiphonous plants leading to monosiphonous 

 growths that again afterwards became polysiphonous. Hamel (1924) had earlier stated that he 

 thought it likely that E. bertholdii, possessing filaments of several rows of cells, passed through 

 'earned* and 'investiens' stages in development. We have accepted Heerebout's contention that 

 Erythrotrichia bertholdii, E. investiens, E. kylinii and E. obscura are all applicable to growth forms 

 within the form range of E. carnea, and therefore are synonyms of the latter. 



Erythrotrichia welwitschii (Rupr.) Batt. 



Namibia (49). 



'. . . Atlantique (de 1'Angleterre a 1'Afrique du sud) . . .' (4). 



