THE 
HEW PflYTOItOGIST. 
Vol. 3, No. 4. Atril 27TH, 1904. 
STUDIES ON ' CYANOPHYCEAE. 
By F. E. Fritsch, B.Sc., Ph. D., F.L.S. 
[With Text-Fig. 76]. 
INTRODUCTORY. 
P ROBABLY no other group of the vegetable kingdom has 
received so little attention from morphologists, as that of the 
Cyanophyceae ; an enumeration of the important papers published 
would not fill much more than a page of this journal. Much atten¬ 
tion has been given to the investigation of the movements of the 
Oscillarieae and at one time or another to the cytological characters 
of the Cyanophyceous cell and to the structure of the sheath, but 
for the rest the greater part of the work has been purely descriptive 
of the fully-developed vegetative structure. The lack of our know¬ 
ledge regarding many essential points in this group, was so obvious, 
and I was confronted by so many problems of interest during my 
examination of the Algal flora of the Royal Botanic Gardens at 
Kew, that I commenced a study of certain features of the group 
nearly two years ago. I propose to embody the results of this 
investigation in the present series. My material was derived from 
the main tank in the Victoria Regia house at Kew and was 
originally intended for the study of an Oedogonium, which was 
present in considerable quantity, blue-green Algae being only repre¬ 
sented in negligible quantities at the time. A month or two later 
the Oedogonium had disappeared almost entirely from the glass 
vessel, in which the material had been placed, and had been 
superseded by a rich growth of blue-green Algae. 
Quite recently Dr. F. Brand (1903) of Munich has published a 
very interesting series of observations, entitled “ Morphologisch- 
physiologische Betrachtungen der Cyanophyceen,” which are based 
pn a ten years’ study of the group in question. Many of my 
