PLATE LVI. 



FIGS. PAGE 



1-3. Cosmarium obsoletum (Hantzscli) Reinsch. 



x 520 . . 133 



4. C. obsoletum. x 520. A large tropical 

 form from Ceylon showing the large pore 

 in the thickening of the basal angles of 

 the semicells. This form has been named 

 "var. Sitvense" by Gutwinski . 134 



5.__C. Smolandicum Lund, x 400 (after 



Lundell) . . 134 



6-7. C. Smolancticum var. angustatum West & 



G. S. West, x 400 . 135 



8-10. C. taxichondriforme Eichler & Gutw. 8, 

 x 750 (after Eichler and Gutwinski) ; 

 9 and 10, x 400 . . 136 



11, 13, 14. C. circulare Reinsch. 11, x 960 (after 



Reinsch) ; 13 and 14, x 400 136 



12. C. circulare forma minor, x 1200 (after 



Raciborski) . . . .137 



