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THE 
y^MERICAN 
Naturalist 
A MONTHLY JOURNAL 
DEVOTED TO THE NATURAL SCIENCES 
IN THEIR WIDEST SENSE. 
SEPTEMBER, 1889. 
No. 273 
CONTENTS. 
ION OF THE OVUM. WITH ESPECIAL 
AGE 
Geology and Pal.ontology.-Th. American Asso-' 
Charles Sedgwick Minot, 
TltE LIFE-HISTORY OF ChOROPHILUS 
■ 
Mineralogy and />^/r^^ra/Ay. — Petrographical 
'^«. O.P.Hay, 
770 
News— Mincralogical News— Rare Minerals 
5(>/a«v.— Botany at the .A.. A. A. S 
V. Language C. L. Webster. 
in the Bay of Fundy-Myxine : a Protandric Herma- 
T. H. Lewis, 
782 
phrodite-Birds Killed by Electric Lights at Gimrd 
"E LOESS Jno. T. Campbell, 
78S 
College, Philadelphia— Zoological News: Coelente- 
rata — Vermes— Arthropoda— Mollusca— Pisces— 
797 
■KS AND "PWIPH ^"''^' 
-TES. 
md Travel.— Xm^uca^: The Gran Chaco 
Physiology.-^StcXs of Stimulating Ner^■e Cells- 
Spinal Ganglia— Voluntary Impulses and Inhibitions, 
P.^.A^/.^.-History of the Owl (continued). . . 
Coast Possessions-Europe: Corsican 
-T— ■.:, P- : r\vx C). .:,.,:. -^^-',.[, ,,:;.; 
.1/.W . - --n-. i^■.:^-^-/^'- '—-,-- - 
PHILADELPHIA: 
FERRIS BROS., PUBLISHERS 
