312 ZYGNEMATACEAE 



PLATE XXXIV 



Spirogvka 



Fig. I. — S. punctata, vegetative cells, gametangia, and zygospores trom 

 China. After Jao. Figs. 2-3. — 5. tsthonua, conjugating filaments and me- 

 dian spore wall, from Estonia. After Skuja. Fig. 4. — S. suomiana, zygo- 

 spore and gametangia from Finland. After Hirn. Figs. 5-6. — 5. puncti- 

 jormis, vegetative cells, zygospores, and spore wall details from Illinois. 

 Figs. 7-8. — S. reflexa, gametangia and zygospores from Illinois. The lower 

 figure illustrates an example of "cross conjugation." Fig. q.^S. micro- 

 punctata, zygospores and gametangia from Illinois. Figs, io-ii. — 5. cor 

 rugata, vegetative cell, conjugating tube, zygospore, and spore wall details. 

 In part after Jao. Fig. 12. — S. hungarica, scalariform conjugation and zygo- 

 spores from Sopron, Hungary. After Langer. Fu;. 13. — S. wabashensis, 

 gametangia and zygospores from Brownsville, Illinois. After Tiffany. 

 Fig. 14. — S. rugulosa, gametangia and zygospores from Bologoe, Russia. 

 After Ivanof. Fig. 15. — S. visenda, vegetative cell, gametangia, and zygo- 

 spore from (x)lumhus, Mississippi. 



