688 THE AMERICAN NATURALIST. | [Vor. XXXV. 
species. The first chapter deals with structure and physiology, the 
second with methods of collection, preparation, and study ; then is 
a historical sketch, with bibliography, dealing with France only. 
Chapter 4 occupies the greater part of the book, giving the general 
principles of classification, followed by description of all known 
French species and forms. A table showing the distribution in the 
different provinces of France and a list of all works cited complete 
the text. There are sixteen plates, containing over eight hundred 
figures. 
It is somewhat singular, considering how much of our best algo- 
logical work is done by French writers, that there has never been 
any general systematic work on French algæ, such as Harvey's 
Manual or Phycologia in Great Britain, Hauck's Deutsches Meeres- 
algen in Germany, and similar works in other countries. This seems 
to be the first work treating of alge, covering the whole of France, 
and giving descriptions of all the species mentioned. It must 
certainly be of much use to French students. 
The classification follows in general that used by De Toni in the 
Sylloge Algarum, but with some modifications. The tribe Docidez 
is united with the Closteriz, while the Micrasteriz retain only the 
forms with chromatophores as parietal disks, the forms having radial 
chromatophores forming the tribe Cosmaria. The form of the 
chromatophores is recognized as of value in classification, but the 
author does not give it the value attributed by Gay. 
A scientific work written by a Frenchman always has one great 
advantage, the “inexorable clearness” of the language ; moreover, 
a French author apparently does not feel that a good style of writ- 
ing will cast doubts on his scientific thoroughness or soundness. 
These merits the work in question has, and also the French pre 
dilection for symmetry ; the description is a description, the note à 
note, and one does not run into the other ; history does not intrude 
into physiological discussion, nor bibliography into directions for 
collecting. 
The plates are clear, every species described being represented, 
mostly by camera drawings by the author. In nearly every case à 
colored figure is given to show the appearance of the living plant, 
and a line drawing to show the markings of the empty cell. Only 
two scales of magnification are used, 200 and 300, and the ne 
scale is used in all the species of a genus, which is very convenient 
for comparison. There is an index, both of accepted names and of 
synonyms. 
