B 
3p A * a 
AMERICAN JOURNAL 
SCIENCE AND ARTS. 
CONDUCTED BY 
PROFESSORS B. SILLIMAN, B. SILLIMAN, Jr., 
AND 
JAMES D. DANA, 
IN CONNECTION WITH 
PROF. ASA GRAY, or CAMBRIDGE, 
PROF. LOUIS AGASSIZ, or CAMBRIDGE, 
DR. WOLCOTT GIBBS, or NEW YORK. 
et, XXIX.—MAY, 1860. 
SECOND SERIES. 
WITH ONE PLATE AND THREE DIAGRAMS. 
NEW HAVEN: EDITORS. 
1860. 
Sse eicncaocinln 
PRINTED BY E. HAYES, 50 CHAPEL sT. 
Mi®s0UR! BOTANICAL 
GARDEN LIBRARY 
