Observations on the Genus Volvox in Africa. 465 



is often inclined a little to one side, the bases are narrow. Two 

 oospores from one coenobium are shown in text-fig. 4, E, drawn on 

 the same scale as the oospores of V. Rousseletii and V . capensis to 

 facilitate comparison. 



Dimensions of V. amboensis sp. nov. 



Mature asexual colony, largest seen 1200 x 1300 p,. 

 Mature sexual colony, 1100 x 1500 /x over 2 mm. 

 Mature daughter colony, 135 x 200 JJL. 

 Somatic cell : anterior pole 20 /x ; posterior pole 10 p. 

 Somatic protoplast, 5 to 7 //,. 

 Number of somatic cells, 30,000 to 50,000. 

 Number of daughter colonies, 1 to 14, most often 7 to 8. 

 Number of sperm globoids not known. 

 Number of oospores, 20 to over 400. 

 Size of sperm globoid, 30 to 33 p.. 



Size of oospore with spines, 40 to 50 /x ; without spines, 30 to 

 37 fj, ; spines, 5 to 7 ^. 



This Volvox is specially noticeable on account of its variability, the 

 large size of the sexual coenobia, the mixed colonies, and the number 

 of rather small oospores with pointed spines. 



In order to compare the species of Volvox referred to in this paper, 

 some of their characteristics have been set out in parallel columns in 

 the table on p. 466. 



SUMMARY. 



In the foregoing paper a short history of Volvox in Africa has been 

 given. 



The occurence of F. aureus Ehrenb. has been noted in several 

 localities from which it was not previously known, viz. the Transvaal 

 (Eliazer Pan, Potchefstroom, and Weltevreden West), Rhodesia 

 (N'gamo and Old N'gamo), and the Bechuanaland Protectorate (vleis 

 and backwaters of the Linyanti River). 



F. africanus, G. S. West, which had been recorded previously only 

 from Albert Nyanza, the Ussangu Desert, and the Philippines, has 

 been described from pools in the neighbourhood of Kazungula on 

 the Linyanti River (asexual only). 



A Volvox from the Cape Flats has been described as a new species, 

 Volvox capensis, intermediate in character between F. globator and 

 T. Rousseletii. A slightly divergent form of this species has been 



