PEOCE EDINGS 



If^Jj^? 



AMERICAN PHILOSOPHICAL SOCIETY 



HELD AT PHILADELPHIA FOR PROMOTING USEFUL KNOWLEDGE. 



Vol. XXXr. April, May, June, 1893. No. 141. 



TABLE OF CONTENTS. 



PAGE 



Stated Meeting, April 7,- 1893 135 



Stated Meeting, April 21, 1893 137 



The Life Histories of Certain Moths of the Families Ceratocain- 

 pidae, Hemileucidfe, etc., with Notes on the Armature of the 



Larvae (with seven plates). By Alpheus S. Packard 139 



Energy as a Factor in Organic Evolution. By John A. Ryder. . . . \^'Z 

 The Mechanical Genesis of the Form of the Fowl's Egg (with one 



cut). By John A. Ryder 203 



Notes on the Classification and Taxonomy of the Testudinata. By 



G. Baur 210 



Stated Meeting, May 5, 1893 226 



Stated Meeting, May 19, 1893 238 



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It^" In order to secure prompt attention it is requested that all corre- 

 spondence be addressed simply "To the Secretaries of the American 

 Philosophical Society, 104 S. Fifth St., Philadelphia." 



Published for the Society 



BY 

 MacCALLA & COMPANY, 



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