22 REPORT OF THE SECRETARY. 



9. Descriptive catalogue of the Corbiculidae or Cydodidae, a group 

 of bivalves principally inhabiting fresh-water, by Temple Prime. 



10. Descriptive catalogue of the Unionidae, or fresh-water mussels. 



11. Descriptive catalogue of the shells of the eastern coast of the 

 United States, b}^ W..Stimpson. 



12. Bibliography of North American conchology, by W. G. Binney. 

 The first and second articles of the foregoing list were printed in 



1860, and described in the report for that year, and since then in 

 their wide distribution have clone good service in facilitating the 

 collecting, labelling, and exchanging of specimens of conchology. 



The third article was published in 1861, as a part of the annual report 

 for 1860, and a new edition v/ill be incorporated in the Miscellaneous 

 Collections as soon as we can procure the long-promised wood-cuts 

 from the British Museum, to illustrate the work. 



The fourth and fifth articles are still in the hands of Mr. Carpen- 

 ter, and will, it is expected, be ready for the press the ensuing year. 



With reference to the sixth article, it may be mentioned that for 

 many years before his death, the late Dr. Amos Binney, of Boston, 

 was engaged in collecting and arranging materials for a general work 

 upon the land shells of the United States. The result of his labors 

 was published after his decease, in three large volumes, giving co- 

 pious descriptions and accurate figures of all the species. His col- 

 lections are now in the hands of his son, Mr. W. G. Binney, of Bur- 

 lington, New Jersey, who has since greatly extended them, and has 

 brought up the subject of his father's work to the present day, by 

 various supplements, memoirs, &c. He has also lately rearranged 

 all the materials in his possession, and prepared from them, for this 

 Institution, the synopsis which is given as the sixth article in the 

 above enumeration. 



The seventh and eighth articles include an account of fresh-water 

 univalves of the United States. Within the last twenty years the 

 number of described species of this class of animals known in this 

 country has greatly increased. The descriptions of these previously 

 made were from specimens collected in isolated situations, oftentimes 

 fey persons who had not had the opportunity of studying large col- 

 lections or of comparing typical specimens, and, indeed, in some 

 cases without access to descriptions which had been previously made 

 by others. The shells belonging to this class are characterized, per- 

 haps above most others, by a remarkable range of variation in form 

 and size arising from local causes, or different stages of growth, &c. 



