The Primitive Algae and the Flagellata. 
An Account of modern Work bearing on 
the Evolution of the Algae. 
BY 
F. FROST BLACKMAN, D.Sc., M.A., 
Lecturer on Botany in the University of Cambridge . 
With two Figures in the Text, 
INTRODUCTION. 
D URING the last fifteen years our knowledge of the 
Algae, especially of the green Algae, has made rapid 
and continuous advance at an increasing rate. As a result 
we seem now at last to be in a position to grasp something of 
the phylogenetic relations of what once seemed a chaos of 
forms, and to correct by the evidence of these vestiges of the 
early stages of evolution of the vegetable kingdom our con¬ 
ceptions of plant nature and plant possibilities drawn pre¬ 
viously only from the study of the higher types. 
The publication ten years ago of Wille’s account of the 
green Algae in the Pflanzenfamilien of Engler and Prantl (’90) 
may be held to mark a definite epoch, as his series of articles 
gathered together and skilfully displayed from the syste¬ 
matic point of view all the knowledge that was then available. 
This most excellent work has given a great impetus to further 
investigation, though we have now advanced beyond it in many 
respects. 
The task that I have undertaken is to give some account 
of the work that has been accumulating on the green Algae 
[Annals of Botany, Vol. XIV. No. LVI. December, 1900,] 
