29 5 
TH H , ; y 
AMERICAN 
JOURNAL OF SCLENCE. 
JAMES D. anp EDWARD 8. DANA. 
ASSOCIATE EDITORS 
Proressors ASA GRAY, JOSIAH P. COOKE, anv 
JOHN TROWBRIDGE, or Campriper, 
Proressors H. A. NEWTON anp A. E. VERRILL, or 
New Haven, 
Prorrssor GEORGE F. BARKER, or PuriLapELpuia. 
THIRD SERIES, 
VOL. XXXIIl—LWHOLE NUMBER, CXXXIII.] 
Nos. 193—198. 
JANUARY TO JUNE, 1887. 
WITH THIRTEEN PLATES. 
NEW HAVEN, CONN.: J. D. & EH, 8. DANA. 
1887. 
