adverti8p:ment. 



The object of the General Appendix to the Annual Report of the 

 Smithsonian Institution is to furnish brief accounts of scientific dis- 

 coveries in particuhir directions; reports of investigations made b}^ 

 collaborators of the Institution, and memoirs of a general character 

 or on special topics that are of interest or value to the numerous 

 correspondents of the Institution. 



It has been a prominent object of the Board of Regents of the 

 Smithsonian Institution, from a very early date, to enrich the annual 

 report required of them by law with memoirs illustrating the more 

 remarkable and important developments in phj'sical and biological 

 discovery, as well as showing the general character of the operations 

 of the Institution; and this purpose has, during the greater part of its 

 histor}', been carried out largely by the publication of such papers as 

 would possess an interest to all attracted by scientitic progress. 



In 18S0 the Secretar}^, induced in part b}^ the discontinuance of an 

 annual summary of progress which for thirty 3'ears previous had been 

 issued by well-known private pul)Hshing tirms, had prepared l)y com- 

 petent collaborators a series of abstracts, showing concisely the prom- 

 inent features of recent scientitic progress in astronomy", geology, 

 meteorolog}", physics, chemistr}', mineralogy, botany, zoology, and 

 anthropologv. This latter plan was continued, though not altogether 

 satisfactorily, down to and including the year 1888. 



In the report for 1889 a return- was made to the earlier method of 

 presenting a miscellaneous selection of papers (some of them original) 

 embracing a considerable range of scientific investigation and discus- 

 sion. This method has been continued in the present report, for 1900. 



121 



