No. 405.] REVIEWS OF RECENT LITERATURE. 761 
88 are plants, and about one-third are reported as common. Like 
that of the Oder, the Elbe plankton is characterized by the predomi- 
nance of diatoms, especially in spring and autumn. In the main 
stream the phytoplankton greatly exceeds the zoóplankton in volume 
and variety and plays a very important part in the self-purification of 
the river water. Access of sewage does not have a deleterious effect 
upon the plankton. Dr. Schorler does not regard the Elbe plank- 
ton as autonomous, but dependent for its maintenance upon accessions 
from adjacent bays and lagoons, and from tributary waters. The 
littoral faana and flora also contribute to the potamoplankton. In 
the still water of the bays an abundant animal plankton of rotifers 
and crustaceans was found, which reached the unusual volume of 
112 C.c. per cubic meter of water. CARK 
ZOOLOGY. 
New Edition of ‘t Wilson's Cell." — The penalty that an author 
must pay for writing a successful text-book is that of revision, and 
this penalty has been conscientiously and fully met by Dr. Wilson? 
in the new edition of his text-book on the cell. The first edition 
was published in 1896 and contained 371 pages and 142 illustra- 
tions. The second edition, now before us, contains upwards of a 
hundred additional pages and nearly fifty new illustrations. Minor 
changes appear on almost every page, and some sections have been 
entirely recast. The more striking changes reflect the steady growth 
of cytological knowledge. Thus, the centrosome, which in the first 
edition was treated as a permanent organ of the cell, is, in view of 
the most recent work on both plants and animals, regarded now as 
of mixed character, in that it sometimes exhibits the peculiarities of 
à permanent organ by being inherited from cell to cell, and at other 
times is strictly temporary. The statements as to the finer structure 
of protoplasm have also been considerably modified. In the first 
edition Dr. Wilson favored the fibrillar theory, though without deny- 
ing that other views might contain more or less truth. In the second 
edition the alveolar theory and even the granular theory have gained 
sufficiently to be fairly abreast their former rival. This change of 
! Wilson, E. B. The Cell in Development and Inheritance. New York, The 
Macmillan Company, i900. Second edition, xxi + 483 pP- 
