THE A = 
AMERICAN 
JOURNAL OF SCIENCE. 
BG. B. SILLIMAN. 
JAMES D. ann E. 8. DANA, anpv B. 
ASSOCIATE EDITO 
Prorrssors ASA GRAY, pea P. COOKE, anp 
JOHN TROWBRIDGE, or Camsriper, 
Prorrssors H. A. NEWTON anp A. E. VERRILL, or 
New Haven, 
Proressor GEORGE F. BARKER, or PHILADELPHIA 
f THIRD SERIES, 
VOL. XXI.—[WHOLE NUMBER, CXX11] 
Nos. 121—126. 
ANUARY TO JUNE, 1881. 
WITH PLATES I TO X AND XII TO XIX 
NEW HAVEN, CONN.: J. D. & E. S. DANA. 
1881. 
Miss30uUR! BOTANICAL 
DEN LIBRARY 
