92 PROCEEDINGS OF THE ACADEMY OF 



April V2th. 

 Dr. Bridges, Vice-President, in the Chair. 



Twenty-two members present. 



The following were presented for publication : 



" Descriptions of six new species of Uuionidae from Lake Nyassa, 

 Central Africa;" "Descriptions of six new species of Succinea," 

 and " Descriptions of thirteen new species of Melanidse." By Isaac 

 Lea. 



"A Critical Review of the Procellaridse, Pt. II." By E. Coues, M. D. 



The death was announced of Samuel Ashmead and William J. Tay- 

 lor, late members of the Academy. 



April 19th. 

 Dr. Bridges, Vice-President, in the Chair. 



Eighteen members present. 



The following were presented for publication : 



" Description of a new species of Planorbis ;" " Descriptions of five 

 new species of Lymnaea ;" " Description of two new species of Union- 

 idae from South Africa," and " Descriptions of twenty-four new species 

 of Physa." By Isaac Lea. 



" Notes of an examination of the Birds of the Group Coerebrinae," 

 etc. By John Cassin. 



April 2bth. 



Dr. Bridges, Vice-President, in the Chair. 



Nineteen members present. 



The following, on favorable report of the respective committees, 

 were ordered to be published : 



Synonymy of the Species of STREPOMATIDiE, a Family of Fluviatile Kollusca 



inhabiting North America. 



Part 3. 



BY GEORGE W. TRYON, JR. 



Genus SCHIZOSTOMA, Lea. 



Schizostoma, Lea, Philos. Proc. ii. p. 242, Dec. 1842, iv. p. 167, Aug. 1845. 



Philos. Trans, x. p. 67, 1847. Obs. iv. p. 41, 1847. Proc. Acad. Nat. 



Sci., May, 1860. Jour. Acad. Nat. Sci. v. pt. 3, p. 245, Mar., 1863. Obs. 



is. p. 67. 

 Schizocheilus, Lea, Philos. Trans, x. p. 295, 1853. Obs. v. p. 51, 1853. 

 Gyrotoma, Shuttleworth, Mittheil, Naturforsch. Bern. p. 88, July 22, 1845. 



Adams, Genera, i. p. 305, Feb., 1854. Gray, Guide to Mollusca, i. p. 103, 



1857. Chenu, Man. de Conchyl. i. p. 293, 1859. Anthony, Proc. Acad. 



Nat. Sci., p. 63, Feb., 1860. Binney, Check List, June, 1860. Brot, 



List, p. 27, 1862. 



[April, 



