To Joseph Henry ^ Esq., LL.D,, Secretary of the Smithsonian Institution : 



Sir : I herewith present to you the report of operations during the year 

 1851, in the departments severally assigned to my charge. These consist 

 mainly of three : 1st, of publications ; 2d, of distribution of volumes and 

 exchanges ; and 3d, of natural history ; and I propose to take them up in 

 the order here named. 



1. PUBLICATIONS. 



During the year 1851 the second volume of Smithsonian Contributions 

 to Knowledge was published, containing four hundred and sixty- four 

 pages of text, twenty-four plates, and eighty-two wood cuts. The print- 

 ing was commenced in 1850 and completed in 1851 ; only a few, how- 

 ever, of the thirteen papers embraced in the volume had left the press 

 before the commencement of the year, while more than one half the matter 

 was not put into the printer's hands until after this period. The following 

 list contains an enumeration of the individual memoirs of the volume, with 

 the number of pages and illustrations to each. It will be remembered that 

 each memoir is separately paged and indexed, and is thus distinct in itself, 

 and that the volume is an aggregate of individual papers, with, however, a 

 general introduction and title, as well as a general alphabetical index to all, 

 in addition to the special index to each memoir. In order to facilitate the 

 application of this general index, the plan used for congressional documents 

 has been adopted for the third volume — namely, to assign beforehand to 

 each paper its place in the series, and to have this number, in Roman let- 

 ter, printed inside of the running head of each page. 



List of Memoirs in Vol. II. t^mithso7iian Contrihutions to Knowledge. 



1. Researches relative to the planet Neptune. By Sears C. Walker, Esq. ; pp. 65. 



2. On the Vocal Sounds of Laura Bridgeman, the blind deaf Mute at Boston, compared 

 with the Elements of Phonetic Language. By Dr. Francis Lieber; pp. 32 and one plate. 



3.* Microscopical Examination of Soundings made by the United States Coast Survey, 

 off the Atlantic coast of the United States. By Professor J. W. Bailey; pp. 16 and one 

 plate. 



4.* Contributions to the Physical Geography of the United States. By Charles Ellet, Jr.; 

 pp. 64, one plate and two wood cuts. 



5. Mosasaurus, and the three allied new Genera, Ilolcodus, Conosaurus, and Ampho- 

 rosteus. By Robert W. Giljbes, M. D. ; pp. 14 and three plates. 



6. The Classification of Insects from cmbryological Data. By Professor L. Agassiz ; pp. 

 28, one plate and eight wood cuts. 



7. On the explosiveness of Nitre, with a view to elucidate its Agency in the explosion of 

 July, 1845, in New York. By Dr. Robert Hare ; pp. '20. 



8.* Microscopical Observations made in South Carolina, Georgia, and Florida. By Pro- 

 fessor J. W. Bailey; pp. 48 and three plates. 



9.* Aboriginal Monuments of the State of New York, comprising the results of original 

 survej's and explorations, with an illustrative appendix. ByE. G. Squier; pp. 188, four- 

 teen plates and seventy-two wood cuts. 



•The asterisk added to the number indicates that the memoir was first issued in 1851. . 



