

ADVERTISEMENT 



The Smithsonian Miscellaneous Collections series contains all the 

 publications of the Institution except the Annual Report, and occa- 

 sional publications of a special 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. Wet MORE, 

 Secretary of the Smithsonian Institution. 



(iii) 



