PLATE XXVII. 



A. MoNORMiA, page 231. 



Fig. 1, portion of the gelatinous fronds, as they appear 

 to the eye. 2, part of a frond; magnified. 3, fila- 

 ment from the same ; highly magnijied. 



B. HoRMOSPORA, page 235. 



Fig. 1, young, and^^. 2, full-grown plant of H. ra- 

 mosa. 3, spore from the same ; all highlg magnijied. 



C. Spirulina, page 229. 



Fig. 1, S. tenuissima ; the stratum as it appears to the 

 eye. 2, filaments fiom the same ; very highly mag- 

 nified. 



D. Sph^rdzyga, page 232. 



Fig. 1, stratum of S. Carmichaelii, as it appears to the 

 eye. 2, a young and an old filament of the same 

 species ; very highly magnified. 



E. Spermoseira, page 233. 



Fig. 1, stratum of S. litorea, as it appears to the eye. 

 2, filaments from the same ; highly magnified. 



