COMPARATIVE ZOOLOGY 



STRUCTURAL AND SYSTEMATIC 



FOR nSE IN 



Scbools an& Colleges 



BY 



JAMES ORTON, A.M., Ph.D. 



IiATR PP.OFK8S0U OP NATURAL IIISTOEY IN TA8SAK OOLT.KGE, C0KBK8P0NUING 



MEMBKK OF THE ACADEMY OF NATURAL 80IHN0KS, PIIILA1>KLPUIA 



AND OF TUB LYCEUM OF NATUUAL IIISTOKY, M. Y., ETC. 



NEW EDITION, REVISED BY 



CHARLES WRIGHT DODGE. M.S. 



FBOFKBSOU OF BIOLOGY IN THE UNIVEESITY OF UOOUKSTBK 



" The education of a naturalist now consists chiefly in learning haw 

 to compare." — Agasbiz 



NEW YORK AND LONDON \^ 



HARPER & BROTHERS PUBLISHERS 



1899 



