J 



VOL. XXXVII, NO. 435 



March, 1903 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 DEVOTED TO THE NATURAL SCIENCES 

 IN THEIR WIDEST SENSE 



CONTENTS 



Page 



I. Antithetic versus Homologous Alternation . . Professor D. H. CAMPBELL 153 

 H. On the Shell of Littorina litorea as Material for the Study of Variation 



Dr. B. P. BIGELOW and ELEANQB P. BATHBTTN 171 



IH. The sense of Hearing in Fiehes Professor G. H. PABKEB 185 



IV. Notes and Literature: General Biology, Baldwin's Fragments, Theoretical 305 



Biology -Zoology, Goett's Zoology A New System of Zoogeography, 209 

 Gardiner's Maldives, A Book on the Birds of the Rockies, Protozoa - 



Botany, Notes. 216 



BOSTON, U. S. A. 



GINN & COMPANY, Publishers 



