Vol. XXXVIII, Nos. 455-456.' November -December, 1904 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOURNAL 

 DEVOTED TO THE NATURAL SCIENCES 

 IN THEIR WIDEST SENSE 



CONTENTS 



I. The Embryological Development of the Skeleton v. — — ^- ^rBiLEY . . . 



II. The Arboreal Ancestry of the Mammalia . . . ■ W. D. MATTH^ 811 



Localized Stages in Common Roadside Plants • JOSEPH A- CTTSHMAlf 819 



IV. An Arrangement of the Families and the Higher 



DB- B. W. SHTTFELDT 



DB- B. W. anurr,i^i 



Observations on Hearing and Smell in Spiders • ANNIE H- PRITCOTTT 859 



vi. Amitosis in the Embryo of Fasciolaria . PBOFESSOR H L- OSBOBJ» «>» 



Vn. The Transplanting of Trout in the Streams of the J*^^'^*. j^^j^f,^ 885 



TXJ.I. A New Species of Diaptomus from Mexico J n^CTR 



IX. Hyla andersonii and Sana virgatipes at Lakehursti New Jersey. W T DAViB 

 X. Notes and Literature: Psychology, Natural Science and Psychology. 

 Criminal Classes — /od/os-/. Fixation of the Eggs of the Crab, C 

 ner-s Uzldxxes —Climatology , M ard's Translation of ''^^'j 



NotS The Journals.^ 

 Xt PubUcations Eeceived . . . - • 



BOSTON, U. S. A. 



GINN & COMPANY, PUBLISHERS 



an BEACON STREET 



