CONTENTS Continued. 



Joseph Leidy, M.D. On a curious Rhizo pod . 



Joseph Leidy, M.D. On Psorosperms in a Mallard Duck 



Joseph Leidy, M.D. On a Mouthless Fish 



Joseph Leidy, M.D. On Ouramceba 



Chas. A. Young. The Occurrence of Celestine in Blair Co., Pa 



Persifor Frazer, Jr. On the Structure of the York Co. Val 



ley Limestone and on Micro-photography of Minerals 

 Elliott Coues, M.D. Synopsis of the Geomyidje . 

 T. A. Conrad. Description of a new Fossil Shell from Peru 



(Plate 22) 



W. G. Binney. On the Jaw and Lingual Membrane of North 



American Terrestrial Pulmonata (Plates 1-14) 



l-JI 

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 127 



128 



130 



139 

 140 



