26 TUFTS COLLEGE STUDIES, VOL. IV, No. 7 



2. Cell entirely enclosed, no prolongation to surface of host. In vari- 

 ous plants, including species of I.fiiina, but not recorded in 

 L. trisulca. 2. C. R'nyanum. 



3. Cell with pointed base. 3. C. Schtnitzii. 



3. Base of cell not pointed. 4. 



4. Cell snbhemispherical, base flattened. 4. C. dcrtnatocolax. 



4. Base of cell not flattened. 5. 



5. Fertile cell elongate-ovoid ; in gelatine of Rivularia colonies. 



8. C. gloeoph Hum. 



5. Cell globose or subglobose. 6. 



6, In tnembranaceous red algae of the Pacific; cells usually 100 n 



diam. or more. 5. C. inclusuw. 



6.. Cell 60 M diam. or less. 7. 



7. Cell 40-60 n diam., entirely included in fronds of Porphyra. 



7. C. Porphyrae. 



7. Cell 30 M diam. or less, partly external, or when immersed having a 

 tube-like projection connecting with the surface. 6. C. Moorei. 



Page 148, cancel generic description of CHLOROCYSTIS, and 

 for C. COHNII (Wright) Reinhardt substitute CHLOROCHY- 

 TRIUM MOOREI Gardner, 1917, p. 382 ; Chlorocystis Cohnii 

 Moore, 1900, p. 100 ; not C. Cohnii Reinhardt, 1885, p. 4, which 

 is Chlorochytrium Rcinhardtii Gardner, 1917, p. 382 ; nor Chlo- 

 rochytrium Cohnii Wright, 1879, p. 355 ; place as No. 6 under 

 CHLOROCHYTRIUM. 



7. C. PORPHYRAE Setchell & Gardner in Gardner, 1917, p. 

 379, PI. XXXII, fig. 6. Cells spherical, 40-60 ft diam., im- 

 bedded in the membrane of Porphyra perforata forma segrtgata 

 Setchell & Hus. on both sides of the median layer of ft-lls ; 

 chromatophore single, at first small, covering the upper part of 

 the cell, increasing by sending out several arms, finally cover- 

 ing the wall ; pyrenoid single, large ; cell wall 2-3 n thick, not 

 laminate; color grass-green: sexual reproduction by biciliate 

 gametes, 3-4 /* diam., fusiform to subspherical, escaping by an 

 oval opening in the wall ; asexual reproduction unknown. 

 Lands End, San Francisco, Cal., Gardner. 



8. C. GLOEOPHILUM Bohlin, 1897, p. 28, PI. I, figs. 53-54; 

 G. F. Moore, 1917, p. 271, PI. XVIII. Vegetative cells sub- 

 spherical, 25-30 n diam., with single parietal chromatophore, 

 usually covering the entire cell wall, with one large pyrenoid ; 

 later developing into an ovoid-oblong sporangium, 50-70 X 25- 

 35 M occasionally even larger; wall 5-10 /* thick, often with 

 irregular prominences, external or internal, which sometimes 

 show lamination; 32-64 spherical aplanospores, 4 /* diam., 



