552 



Annals of the South African Museum. 



had a very obscurely punctate membrane, although generally nothing 

 of the kind could be discerned. 



4. Costnarium holmiense, Lundell, Desni. Suec, Nov. Act. reg. soc. 

 scient. Upsala, Ser. 3, viii, 1871, p. 49, Tab. II, fig. 20; W. & G. S. 

 West, op. cit, iii, 1908, p. 1, PI. LXV, figs. 1, 2. 



Forma ad var. integrum, Lund, accedens. Long., 54-58 /x; lat., 

 33-35 fx- lat. isthm., 15-17/* (Pig. 27). 



Sample 50 (very rare). 



Only two specimens were observed which agreed with the type, 

 except in the nature of the apices ; these were either slightly refuse or 

 slightly convex, the two forms occurring on the two semicells of the 

 same individual (Pig. 27). These specimens should be compared with 



5 5p- 



Fig. 27. — Costnarium holmiense, Lund., forma. 



a form of var. integrum, Lund., described by Borge (Beitr. z. Algeufl. 

 v. Schweden, 2, Bot, Notiser, 1913, p. 16, Tab. I, fig. 10), which, how- 

 ever, lacks the small undulations of the lateral margins. 



5. Cosmarium obtusatum, Schmidle, Engler's Bot. Jahrb., xxvi, 1898, 

 p. 38 ; W. & G. S. West, op. cit., iii, 1908, p. 7, PI. LXV, figs. 13. 14. 



Sample 32 (rare). 



Side by side with specimens showing typical dimensions (lung., 

 03 /i ; lat,, 51 ,x; lat. isthm., 15/*), others were observed which were 

 relatively broader (long., 66 /*; lat. ,00,/; lat. isthm., 15/0). Theapex 

 was moreover, in some cases, faintly undulate. It is possible that these 

 variations indicate a distinct form. C. obtusatum has been recorded 

 from the Karoo by G. S. West. 



0. Gosmarium quadratum, Ralfs ; W. A G, S. West, op. cit.. iii. 1908, 

 p. 57. PI. LXX, tigs. 0-8. 



