PLATE LXXXIII. 



FIQ-S. PAGE 



1. Cosmarium Turpinii Breb. Vertical view, x 500 189 

 2. C. Turpinii var. podolicum Grutw. x 500 . 191 

 3. C. Turpinii var. eximium W. & Gr. S. West. 



x 500 . . . . 192 



4-11. C. margaritiferum Menegh. 4-9, various forms 

 from widely separated localities, x 500 ; 10, 

 zygospore from Thursley Common, Surrey, 

 x 400; 11, zygospore from Harris, Outer 

 Hebrides, x 500 . . .199 



The cell-wall is minutely punctulate be- 

 tween the granules, but these punctulations 

 are not well shown in the figures. 

 12. C. margaritiferum forma regular lor (Nordst.) 



nob. x 570 (after Nordstedt) . . 203 



13. C. margaritiferum forma Kirchneri (Borges.) 

 nob. a and b, x about 660 ; a', x about 190 

 (after Borgesen) . . . 203 



