342 THE AMERICAN NATURALIST. [Vor. XXXIX. 
and the Cladocera by Dr. Apstein; the echinoderm larve by Dr. 
Th. Mortensen ; the Foraminifera by Professor Rhumbler ; and the 
Tripylea (= Phxodaria Hkl.) by Dr. Borgert. Part II contains the 
Ctenophora by Dr. Vanhóffen; the Schizophycez by Prof. N. Wille ; 
and the Flagellatze, Chlorophycez. Coccosphzerales, and Silicoflagel- 
late by Dr. E. Lemmermann. 
As usual in works of composite authorship we find here consider- 
able variety in the method and form of treatment, especially in mat- 
ters of literature and synonymy. The admission of a large number 
of fresh-water species in the sections dealing with the Schizophycez, 
Chlorophycex, and Flagellatze seems illadvised. They occur in 
brackish waters only and are generally adventitious even there, and 
have no part in the marine plankton. The authors of the sections 
dealing with the Ostracoda and Cladocera have excluded all adven- 
titious forms from fresh water. Itisto be hoped that the appear- 
ance of the remaining parts of this most useful manual may not be 
long delayed. 
CAK. 
Wild Birds and their Music.'— Notwithstanding the present-day 
abundance of popular guides to the study of our native birds, Mr. 
Mathews has found an almost untouched field in preparing a guide 
to the songs of the commoner species of the eastern United States. 
In this artistic little volume of 262 pages, the songs and character- 
istic notes of 82 species are carefully analyzed and set down in 
musical notation or in line and dot diagrams, and these are so 
explained as to be quite intelligible, even to one who has no techni- 
cal knowledge of music. To the beginner in bird study, who finds 
it much easier to hear birds than to see them, this book cannot fail to 
be an aid in identifying the commoner song-birds. In addition to the 
musical description, a brief diagnosis of each species is added, 
together with a statement of its distribution. A number of plates in 
wash or in color illustrate nearly all the birds described in the text. 
All these are from drawings by the author, and although many of 
them are admirable, others have evidently suffered much in the 
reproduction. A good index enhances the value of this book for 
field use. 
GM A. 
1 Mathews, F, Schuyler. Field Book of Wild Birds and their Music. New 
York; G. P. Putnam’s Sons, 1904. 16mo, xxxv + 262 pp., illus. $2.00. 
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