596 Am/ah of the South African Museum. 



Var. proboseidea, Grun. ; Van Heurck, op. cit, p. 140, PL XXXI, 



fig. 10. 



Samples 29, 29«, 30a, 31. 



Long., 57-60 /x ; Int., 11 /x. 



4. Epithemia gibberula, Kuetz. ; Van Heurck, op. cit., p. 140. (Syn. : 

 Rhopalodia gibberula (Kuetz.), O.Muell.) 



Samples 4, 5, 6. 



Eecorded from the Karroo by G. S. West, 



D. NITZSCHIOIDEAE. 



Genus NITZSCHIA Hassall. 



Section TRYBLIONELLA Getjnow. 



1. Nitzschia tryblionella, Hantzsch ; Van Heurck, op. cit., p. 171, 

 PI. LVII, figs. 9, 10. (Tryblionella hantzschiana, Grim.) 



Var. levidensis (W. Sm.), Grun.; Van Heurck, op. cit., p. 171, 

 PL LVII, fig. 15. (Syn. : Tryblionella levidensis, W. Smith, op. cit., ii, 

 p. 89.) (Fig. 41, e.) 



Samples 4, 6. 



Long., 30-50 \i ; lat., 12-16 /x. Many of the individuals were 

 slightly constricted in the middle. The markings on the surface of 

 the valves are of a very irregular nature, appearing as short undulating 

 lines extending from 'one edge a little more than half way across, 

 the lines from opposite edges alternating in an irregular manner. 



(Fig. 41, e.) 



The type has been recorded from the Halle River, Calvinia Division, 



by G. S! West. 



Section APICULATAE Grtjnow. 



1. Nitzschia. hungarica, Grun.; Van Heurck, op. cit., p. 173, PL 

 LVIII, figs. 19-22. (Fig. 41, d.) 



Samples 25, 32, 48. 



Long., 57-93^; lat., 8-9 [x. The characteristic interruption of the 

 striae in the middle part of the valve, due to the presence of a fold, 

 was very well marked (Fig. 41, d) ; in the region of interruption the 

 striae are sometimes very faintly recognisable. In several of the 

 specimens a few of the striae in the central part of the valve could be 

 traced right across (Fig. 41, d). The carinal dots are very faint. The 

 apices are slightly curved to one side. 



