EXTEACTS FROM THE CORRESPONDENCE OF THE INSTITUTION TO ILLUS- 

 TRATE ITS OPERATIONS, ADDRESSED TO THE SECRETARY, PROFESSOR 

 JOSEPH HENRY. 



From Joseph Leidy, Curator Academy of "Natural Sciences. 



Philadelphia, May 1, 1866. 



Dear Sir : I write in answer to your letter of February 20, in relation to 

 the donation of shells by the Smithsonian Institution to the Academy of Natural 

 Sciences. I was obliged to wait until now to give the committee an opportunity 

 to make out an account of the shells, which account I have just received from 

 the chairman, Mr. Tryon. He reports as follows : 



" The collection of shells recently presented to the Academy of Natural Sci- 

 ences by the Smithsonian Institution embraces over 1,300 species, of which 793 

 are new to our collection ; an extraordinary increase, due in great part to the fact 

 that many of the species are those collected by the Wilkes exploring expe- 

 dition, (described by Dr. Gould,) never before distributed. There are also a 

 large number of new species from the west coast of North America, recently de- 

 scribed by Mr. Carpenter. 



"We were indebted to the Smithsonian Institution last flill for a donation of 

 800 species, including 300 new to our collection, being a first portion of the ex- 

 pedition shells. Uniting the two donations, we have thus received over 2,100 

 species, including 1,100 new to us, within six months. The accuracy of the 

 names and localities renders the collection a valuable addition to our museum." 



From J. Miguel Arroyo, Perpetual Secretary of the Mexican Society of Geog- 

 raphy and Statistics. 



Mexico, March 24, 1865. 

 Esteemed Sir : This society has been highly gratified by the communication 

 of your note of November last, in which notice is given it of the books which the 

 Smithsonian Institution has had the goodness to remit. In effect, it has just 

 received, at the hands of Senor D. Jose Ramon Pacheco, three large boxes con- 

 taining the said books, which the society, with a high appreciation of the gift, 

 has ordered to be placed in its library as a valuable addition to the collection 

 which it already possesses regarding the United States. I shall not forget to 

 seek, and will very soon send you the " Registro trimestro," which you have 

 had the condescension to inquire for ; and begging you to accept for your distin- 

 guished institution the thanks of this society fi)r the favor conferred, I have the 

 honor to subscribe myself your obedient servant. 



From Jno. Evans, Governor of Colorado Territory. 



Denver, July 29, 1865. 

 Dear Sir : The fossil jaw referred to in yours of the 12th instant was pre- 

 sented to me by Arapahoe Chief "Friday," who said he found it on Rock creek, 

 a tributary of the Republican fork of the Kansas river, about one hundred and 

 fifty miles nearly due cast of this place. 



