CYANOPHYCEA 261 
of roundish oval or pyriform cells grouped together. 
There is no vegetative propagation known, but the 
cells become sporangia in the fashion described for 
Hyella. 
The Geographical Distribution of Chroococcacce is 
world-wide. Gleocapsa, Polycystis, Hyella, and Dermo- 
carpa, occur in British seas. The two last genera are 
marine only ; Hyel/a known only in European waters, 
but Dermocarpa with a wider range. 
