38 THE ALGAE 



where it starts life as a quadriflagellate swarmer of the chlamydo- 

 monad type. When the swarmer comes to rest with attachment 

 papillae at the base, a new wall is formed. The apex of the old wall 

 ruptures, the cell contents develop two flagella and the motile 

 body moves up with its new wall imtil it becomes enclosed in the 

 neck of the old one. The flagella are then lost for a time and then 

 the process is repeated so that gradually a filament of dead en- 

 velopes is built up. An obhque division of the hving cell results in 

 branch formation, or after horizontal division the lower half may 

 be left behind in the middle of the dead cells. It is evident that at 

 each division a swarmer is formed that is not normally liberated. 

 On the few occasions when it is Uberated the species is perpetuated, 

 but at present the conditions under which liberation occurs are not 

 known. 



REFERENCES 



Volvocaceae 



Cave, M. S. and Pocock, M. A. (1951)- Amer.J. Bot. 38 (10), 800. 

 Stein, J. R. (1958), Amer. J. Bot. 45 (5)3 388. 



Sphaerella 



Elliott, A.M. (1934). Arch. Protistenk., 82, 250. 



Volvocales 



Fritsch, F. E. (1935). Structure and Reproduction of the Algae, Vol. I, 

 pp. 77-144. Camb. Univ. Press. , 



Pleodorina 



Iyengar, M. O. P. and Ramanathan, K. R. (1951)- Phytomorph., J, 3/4, 

 215. 



Wall structure 



Nicolai, E. and Preston, R. D. (1952). Proc. Roy. Soc. Lond., ser. B, 

 J40, 244. 



Volvox 

 Pocock, M. A. (1933). Ann. S. Afr. Mus., 16, 523. 

 Pocock, M. A. (1938). Quekett Micr. Club, ser. 4, J, i. 



Eudorina 



Doraiswami, S. (1940). J. Ind. Bot. Soc, 19, 113. 



Schizochlamys 

 Thompson, R. H. (1956). Amer.J. Bot., 43, 665. 



