EXPLANATIONS AND REFERENCES, 

 PLATE CLXVI. 



Figures variously magnified. 



PAGE. 

 Fig. 1 . PORPHYRIDIUM CRUENTUM, a very small portion of a thallus, 1 94 



" 2-8. GLOEOCYSTIS AMPLA, variety of cells, . . 1 96 



" 9-15. GLOEOCYSTIS VESICULOSA, ..... 196 



" 16-18. GLOEOCYSTIS RUFESCENS, . . . . .196 



" 19-21. GLOEOCYSTIS RUPESTRIS, ..... 196 



