1883.] NATURAL SCIENCES OP PHILADELPHIA. 39 



January 30. 

 The President, Dr. Leidy, in the chair. 

 Twenty-eight persons present. 



The following papers were presented for publication : — 



" TJrnatella gracilis," by Joseph Leidy, M. D. 



" On the Extinct Peccaries of North America," by Joseph 

 Leidy, M. D. 



" The Terrestrial Mollusca inhabiting the Societ}'^ Islands," by 

 Andrew Garrett. 



The death of John Wister, a member, was announced. 



Hybrid Birds. — Chas. Townsend referred to the rare occurrence 

 of hybridit}^ among N. Am. Passeres^ and stated that two species 

 of native warblers had recently been found to be hybrids, between 

 species of the genus Helminthophaga. He exhibited a bird taken 

 by Mr. W. L. Baily in Dec, 1882, near Haverford College, Pa., 

 which proved to be a hybrid between the Snowbird and the 

 White-throated Sparrow, birds of different genera, which was 

 more remarkable. 



After referring to the marks of hybrid origin borne by some 

 doubtful species, handed down by the earlier ornithologists, he 

 remarked that hybridity would doubtless be found a sufficient 

 explanation for many obscure species that are standing puzzles 

 to the ornithologists of to-day. 



Mr. Chas. Morris was elected a member of the Council, to fill the 

 vacancy caused by the election of Dr. Ruschenberger as Curator. 



The following were elected members : — 



F. A. Genth, Jr., Clarence R. Claghorn, G. Howard Parker, 

 John B. Deaver, M. D., Wm. L. Springs, H. T. Cresson, Jacob L. 

 Wortman and Emily G. Hunt. 



February 6. 



The President, Dr. Leidy, in the chair. 



Twent3'-three persons present. 



A paper entitled "A new Extinct Genus of Sirenia," by Edw. 

 D. Cope, was presented for publication. 



