PLATE LXXI. 



FIGS. PAGE 



1-2. Cosmarium minimum W. & G. 8. West. 1, 



x 830; 2, x 520 . . .66 



3-4. C. pnsillnm (Breb.) Arch. 3, x 520; 4, x 



1000. . . . .66 



5-6. C. geometric-urn W. & G-. S. West. 5, x 520 ; 



6, x 1000 . . . .67 



7. C. helcangulare Nordst. x 920 (after Nord- 



stedt) . . . .68 



8. C. coarctatum West. x 520 . .69 



V. C. protuberans Lund. x 400 (after Lnndell) . 69 

 10. C. protuberans forma paludosa W. & G. S. West. 



x 520 . . . . 70 



11-14. C. Sphagnicolum W. & G. S. West. 11-13, 



x 520; 14, x 1000 . . .71 



15-16. C.truncatellumPerty. 15, x 520; 16, x 1000 72 

 17. C. subcapitulum West. x 520 . . 73 



18. C. Capituluml&oy & Biss. x 600 (after Roy & 



Bissett) . . . .119 



19-21. C. Capitulum var. groenlandicum Bo'rges. 



x 520. Fig. 21a is acellina state of division 120 

 22-31. C. pygmteum Arch. 22 and 23, x 520 ; 24-26, 

 x 1000 ; 27 and 28, zygospores, x 520 ; 29- 

 31, x 1240. Figs. 29-31 are after drawings 

 kindly sent to us by Dr. J. Liitkemuller . 73 

 32-34. C. polygonum (Nag.) Arch. 32 and 33, x 520; 



34, after Nageli (a, x 400 ; a', x 600) . 76 



35. (7. pseudobiremum Boldt. x 400 (after Boldt) 77 

 36-37. C. bireme Nordst. 36, x 570 (after Nord- 



stedt) ; 37, x 520 . . .77 



38. C. adoxum W. & G. S. West, x 740 . 78 



39. C.SinostegosSch&arschm. x 800 (after Schaar- 



schmidt) . . . .79 



40. C. Sinostegos var. dbtusius Gutw. x 830 . 79 



