ee a ee 
ADVERTISEMENT. . 
The present series, entitled ‘‘ Smithsonian Miscellaneous Collec- 
tions,” is intended to embrace all the publications issued directly by 
the Smithsonian Institution in octavo form; those in quarto constitut- 
ing the ‘‘ Smithsonian Contributions to Knowledge.” The quarto 
series includes memoirs, embracing the records of extended original 
investigations and researches, resulting in what are believed to be new 
truths, and constituting positive additions to the sum of human knowl- 
edge. The octavo series is designed to contain reports on the present 
state of our knowledge of particular branches of science; instructions 
for collecting and digesting facts and materials for research; lists and 
synopses of species of the organic and inorganic world; museum cata- 
logues; reports of explorations; aids to bibliographical investigations, 
ete., generally prepared at the express request of the Institution, and 
at its expense. 
In the Smithsonian Contributions to Knowledge, as well as in the 
present series, each article is separately paged and indexed, and the 
actual date of its publication is that given on its special title-page, and 
not that of the volume in which it is placed. In many cases works 
have been published and largely distributed, years before their com- 
bination into volumes. 
: DNL EY, 
' Secretary S. 1. 
II! 
