506 



Annals of the South African Museum. 



regularity of development and arrangement of the constituent groups 

 of cells ; the almost perfect spheres with their symmetrically placed 

 groups of equal numbers of equally spaced similar cells are very 

 beautiful objects, and very different from the spheres containing 

 groups at all stages of development characteristic of Chodat's species ; 

 this irregularity of development is well shown in the figures accom- 

 panying his description (18976, pi. ix, particularly figs. 1, 5, and 

 7), and was so striking that Chodat made special mention of it as a 

 characteristic feature of the species. 



The following examples are chosen from the many examined to 

 give an idea of the spherical colonies : 



C. PROTOCOCCALES, SCENEDESMACEAE. 



Genus KIRCHNERIELLA Schmidle. 



Kirchneriella africana sp. nov. 



(Fig. 7, and Plate XXXV, G, H.) 



Familiae magnae, usque ad 2-4 mm. longis, juvenae fere rotundae, 

 maturae plerurnque fere teretes saepe lobatae vel ramosae; cellulis 

 permultis, in tegumento gelatinoso hyalino sine regula dispositis, 

 magnitudine variis; cellula trilobata, basi rotunda, apice profunde 

 emarginato, lobis lateralibus divergentibus, interdum sub-recurvis; 



