Notes on Freshwater Algce. 255 
Fig. 1, A—H. 
A—C. Pyramimonas inconstans sp. n. Various forms of vegetative individuals. 
D. Anterior view of motile cell of P. inconstans , showing sub-quadrate form, 
stigma and the two contractile vacuoles (the cilia are not shown). 
E. Optical longitudinal section of P. inconstans, showing the form xrf the 
chloroplast in long, sect., and the basal pyrenoid. 
F. Non-motile individual of P. inconstans ; s. stigma, c.v. the two contractile 
vacuoles, p. pyrenoid, g. thick hyaline gelatinous investment, 
G. Zoogonidium of Oedogonium cryptoporum, killed with a drop of dilute iodine 
solution. 
H. Diagram illustrating mode of progression of the zoogonidium of 
0, cryptoporum (described in text). 
A—F x I2o0 ; G, HX900. 
