1848.] 



Zoological. 

 Robert E. Griffith, John Cassin, 



S. S. Haldeman, Edward Harris, 



Edward Hallowell, William Gambel, 



Joseph Leidy. 



Botanical. 

 Robert Brid,g;es, R. E. Griffith, 



William S. Zantzinger, Gavin Watson, 



Robert Kilvington. 



Physics. 

 Walter R. Johnson, John S. Phillips, 



Paul B. Goddard, Thomas G. Percival, 



Samuel Powel. 



Library. 

 R. Bridges. T. C. Percival, 



S. B. Ashmead, Benjamin J. Kern, 



M. Carey Lea. 



Committee on Proceedings. 

 S. G. Morton, C Corresponding and 



J. S. Phillips, A Recording Secretaries, 



W. S. Zantzinger, (_ ex-officio. 



Caleb Cope, Esq., William H. Dillingham, Esq., John Cooke, Esq., 

 and the Rev. Kingston Goddard, of Philadelphia, and Robert Haines, 

 Esq., of Germantown, were elected Members, and Dr. William Max- 

 well Wood, U. S. N., was elected a Correspondent, 



February 1st, 1848. 



Vice President Morton in the Chair. 



A communication was presented, entitled, " Descriptions of some 

 new plants collected by Mr. William Gambel in the Rocky Mountains, 

 and California, by Thomas Nuttall, F. L. S.'' Referred to Dr. Bridges, 

 Mr. Gambel, and Dr. Zantzinger. 



Dr. Leidy read a paper " On some peculiar bodies in the Boa Con- 

 strictor, resembling the Pacinian corpuscles," which was referred to a 

 committee, consisting of Drs. Hallowell, Morton, and Bridges. 



Mr. Cassin, referring the Academy to a paper by Professor Percy, " On the 

 management of Monkeys in captivity," published in the Proceedings of the Zoo- 

 logical Society of London, for 1844, made some remarks on that subject. 



He characterized Prof. Percy's observations, as highly judicious and evidently 

 the result of much experience, — he (Mr. C.) wished however to point out the 

 fact, that in the enumeration of articles suitable for the diet of those animals in 

 confmement. Prof. P. had mentioned no animal food, except milk, an omission 

 difficult to account for, as Prof. P. observes in the same paper, " the Marmozet 

 eats spiders with great avidity." 



Mr. C. stated that it was a well known fact, that many of the American 

 species fed not upon fruit solely, but also upon insects, bird's eggs, and even 



