V ; I 1 L/ 



ADVKRTISKMENT 



The Smithsonian Miscellaneous Collections series contains, since the 

 suspension in 1916 of the Smithsonian Contributions to Knowledge, 

 all the i)ublications of the Institution except the Annual Report, the 

 annual volume descrihinj^' the Institution's field work, and occasional 

 jnihlications of a sj>ccial nature. As the name of the series implies, its 

 scope is not limited, and the volumes thus far issued relate to nearly 

 every branch of science. Papers in the fields of biology, geology, 

 anthropology, and astrophysics have predominated. 



A. Wf.tmore, 

 Secretary of the Sniitlisonia)i Institution. 



(iii) 



