The Freshwater Algae of Africa. 505 



(4) HYDRODICTYACEAH. 



Genus PEDIASTEUM Meyen. 



1. Pedia8trum tetras (Elirenb.), Ralfs. Ann. and Mag. Nat. Hist., 

 xiv, 1844, p. 469, PL XII, fig. 4; Brit. Desm., 1848, p. 182, 

 Tab. XXXI, fig. 1 (Syn. : P. ehrenbergii, Corda, Alman. <le Carlsbad, 

 1839, p. 138, Tab. II, fig. 8). 



Sample 39 (rare). 



2. Pediastru/m duplex, Meyen, Nov. Act. Leop. -Carol. Ak., xiv, 

 1829, p. 772, PL XLIII, figs. 6-20 (Syn. : P. pertusum, Kuetz.). 



Sample 39 (rare), 48 (very rare). 



Var. reticulatum, Lagerheim, Ofvers. K. Vet.-Akad. FoerliandL, 

 1882, No. 2, p. 56, Tab. II, fig. 1. 

 Samples 14 and 15 (very rare). 



3. Pediastrum boryanwm (Turp.), Menegh., Monogr. nostoch. ItaL, 

 Att. R. Ac. Sci. Torino, Ser. 2, v, p. 210. 



Sample 18 (rare). 



Recorded from the Karroo by Or. S. West. 



Genus HYDROPICTYON Roth. 



1. Hydrodictyon africaniim, Yamanouchi, Bot. Gaz., lv, 1913, pp. 74- 

 79. figs. 1-6. 



Sample 20 (N.B. — This is not the same locality as that from which 

 Yamanonchi has recorded the species). 



The material was in an early stage of development, the broadly oval 

 coenocytes being arranged to form marked nets. Long, coenocyt., 

 1430-1650 fi ; lat. coenocyt. ad med., 715-780 /x. A few slightly 

 older stages, in which the constriction between the coenocytes was 

 more pronounced, were also observed. This species is evidently quite 

 common in the Cape Peninsula, as the writer has material from various 

 localities and hopes to be able to extend Yamanouchi's description in a 

 subsequent communication. 



(5) CHLORELLACEAE. 



Genus TROCHISCIA Kuetzing. 



1. Trochiscia aspera (Reinsch), Hansgirg, Ueb. d. Suesswasseralg.- 

 Gatt. Trochiscia, etc., Hedwigia, xxvii, 1888, p. 128 (Syn. : Acantho- 

 coccus a$per, Reinsch). 



Sample 21 (rare). 



