26 KEPOET OF THE SECRETARY, 



human remains or sepulchral mounds have been discovered, nor any 

 evidence of the cultivation of the soil. From the extent of the works, 

 and the difference in their apparent antiquity, it is probable that a 

 large number of individuals were engaged, and during a long succes- 

 sion of years. 



Miscellaneous Collections. — The Miscellaneous Collections include 

 works intended to facilitate the study of the various branches of 

 natural history, to give instruction as to the method of observing 

 natural phenomena, and a variety of other matter connected with the 

 progress of science. Although the object of the Institution is not 

 educational, yet in carrying out the general plan it has been thought 

 important in some cases to publish elementary treatises, which Avill 

 not only furnish an introduction to special subjects to those who have 

 not access to expensive libraries, but also serve to point out the way 

 in which individuals by special studies can not only promote their 

 own enjoyment, but also co-operate with all others engaged in the 

 same pursuit in extending the domain of knowledge. The objects of 

 nature, like the specimens of high art, are the luxuries of the culti- 

 vated mind, and the awakening of a taste for their study affords an 

 inexhaustible source of pleasure and contentment to the most nume- 

 rous and the most important classes of the community. 



In accordance with this view it was stated in the last report that 

 the following works were in preparation to introduce and facilitate 

 the study of conchology, a branch of natural history not only inter- 

 esting in itself, but also indispensable in the study of geology, as the 

 ages and relative position of rocks are principally determined by the 

 remains of this class of animals, which are found imbedded in their 

 strata: 



1st. Elementary introduction to the study of conchology, by P. P. 

 Carpenter, of England. 



2d. List of the species of shells collected by the United States 

 exploring expedition, by the same author. 



3d. Descriptive catalogue of the shells of the west coast of the 

 United States, Mexico, and Central America, by the same author. 



4th. Bibliography of North American conchology, by W. G. Binney. 



5th. Descriptive catalogue of the air-breathing shells of North 

 America, by the same author. 



The first of these works was published as a part of the appendix 

 to the report of the Regents for 1860, and, in order to meet the 



