10 PROCEEDINGS OF THE ACADEMY OF [1896. 



The following minute was unanimously adopted : 

 In view of the fact that General Isaac J. Wistar has served 

 four consecutive years, the limit defined by the By-Laws, as Presi- 

 dent of the Academy of Natural Sciences of Philadelphia, his 

 fellow members desire to indicate their esteem and affection by a 

 cordial endorsement of the minute of recognition adopted by the 

 Council and to express the hope that the Academy may long profit 

 by the clearness of judgment, the knowledge of affairs and the 

 courtesy of personal intercourse which have been the characteristics 

 of his administration. 



Dr. Benjamin Sharp made a second communication on his 

 ethnological studies in Alaska and Siberia. (No abstract). 



January 14. 



The President, Samuel G. Dixon, M. D., in the Chair. 



Thirty-four persons present. 



The death of Samuel G. Lewis, a member, was announced. 



A paper entitled " New Species of the Helicoid Genus Polygyra," 

 by H. A. Pilsbry, was presented for publication. 



Pleurotomaria erotaloides Morton in the New Jersey Cretaceous. — 

 Mr. H. a. Pilsbry exhibited a fossil Pleurotomaria from Mullica 

 Hill, New Jersey, found by Henry L. Balderston when on a excur- 

 sion of the geological class of Westtown School, and submitted to 

 the speaker by Lewis Woolman. ^ 



The specimen is an internal cast and has lost the earlier whorls. 

 Enough remains, however, to distinguish it as a strongly marked 

 species, apparently identical with Cirrus erotaloides Morton\ des- 

 cribed from Erie, Alabama. 



The species has not been noticed since its original publication in 

 1834, and as Morton's description is very brief (less than three 

 lines long) and involves a grave inaccuracy, and his figure is 

 decidedly uncharacteristic, a more detailed description of the spec- 

 imen discovered by Mr. Balderston is here given, followed by notes 

 on Morton's type specimen. It may be described as follows : 

 Pleurotomaria crotaloides Morton. (Plate I). 



Shell (cast) rather discoidal, the spire low-conic, base flattened 

 and very broadly umbilicated. Whorls slowly increasing, very 

 convex, separated by deep sutures ; the last whorl strongly convex 

 on the upper surface, thence sloping outward to the periphery, which 

 is quite convex again, and near the base of the whorl. Base dis- 



* Synopsis of the Organic Remains of the Cretaceous Group of the U. S. 

 p. 49, pi. 19, fig. 5. 



