294 THE JOURNAL OF BOTANY 
G 
In this interesting publication, Professor Chodat analyses the 
views of many other authors on the subject of polymorphism in 
Etude erttique et expérimentale sur le Polymorphisme des Algues. 
By R. Cuopat. Genéve. 1909. 
e sets out to answer the following questions :— Are Algee 
po i rphism proved (or verified)? Are 
there, on the contrary, Algz of remarkably stable character? Can 
polymorphic states of higher Alge?” He then gives the results 
of a considerable amount of experimental work on the lower 
forms of green Alge. This experimental investigation is the 
most important part of Professor Chodat’s work, as he has applied 
the method of pure culture to the elucidation of the problem of 
polymorphism. From this careful experimental work he con- 
cludes that there are many low types of green Algw of a very 
stable character, and with his general conclusions (on p. 165) I 
thoroughly agree, as I have myself expressed similar views 
re 
mai uu under various condi- 
tions, have shown that alongside the polymorphic Algw there are 
ways as many, if not more, which present a remarkable stability. 
For this reason we cannot believe that it is justifiable to speak in 
a general manner of a ‘theory of polymorphism of Alge.’” 
part of the work will probably receive much criticism. 
The weakest part of the proposed classification is the inclusion 
within the Pheophycee of the Confervales, the Peridinieg, the 
Bacillariez, and the Euglenacee. The first-named is the chief 
order of the Heterokonte, a group now widely recognised as a very 
natural assemblage. The Peridiniee and the Bacillariee are two 
groups of obscure affinities, possibly somewhat remotely allied to 
each other, but having nothing in common with the Brown Sea- 
