PLATE CXXXVI. 



FIGS. PAGE 



1 . Staurastrum Hystrix Ralfs. X 520 . . 60 

 2-6. St. teliferum Ralfs. 2*, X 510 ; 3, X 520 ; 4, X 

 400 ; 5*, X 510 ; 6, zygospore formed by con- 

 jugation of 3 individuals, x 400 . . 58 

 7. St. teliferum forma obtusa West. X 400 . 60 

 8-10. St. polytrichum Perty. 8, X 520; 9, X 400; 



10*, X 510 . . .53 

 11. St. polytriclmm var. readingense Cushman. Zygo- 

 spore, X 450 (after Cushman) . . 54 

 12. St. erostellum W. & G. S. W. X 660 . . 72 

 13-14. -St. setigerum Cleve. X 500 . . 52 



