PLATE LXXXI. 



FIGS. PAGE 



1. Cosmarium Etchachanense Roy & Biss. x 600 



(after Roy & Bissett) . . .170 



2-3. C. trachypleurum Lund. 2, x 400 (after 



Lundell); 3, x 520 . . 172 



45. C. trncliypleurum var. minus Racib. 4 ; x 600 



(after Roy & Bissett) ; 5, x 520 . .173 



6. C. Slewdrumense Roy. x 600 (after Roy & 



Bissett) . . . .171 



7. C. isthmochondrum ISTordst. x 400 (after Nord- 



stedt) . . ' . .173 



8. C. isthmochondrum var. pergranulatum West 



& G-. S. West, x 400 . . . 174 



9. C. jenisejense Boldt. x 400 (after Boldt) . 175 

 10-11. C. furcatospermum West & Gr. S. West. 10 ? x 

 520; 11, semicell, x 1000. [Consult PL 

 LXXXIV, figs. 8-10.] . . .206 



12-14. C. sphalerostichum Norclst. 12,, x 570 (after 



Nordstedt) ; 13 and 14, x 520 . 176 



15. C. geminatum Lund. x 400 (after Lundell) . 177 

 16. C. Denotarisii (Wittr.) Nordst. x about 500 



(after De Notaris) . . .124 



This figure is a copy of the one given by 

 De Notaris, but we think the side view is 

 incorrect, the constriction not being suffi- 

 ciently deep. 



