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THE 
AMERICAN 
NATURALIST 
A MONTHLY JOURNAL 
DEVOTED TO THE NATURAL SCIENCES 
IN THEIR WIDEST SENSE. 
MANAGING EDITORS: 
Prors. E. D. COPE, Philadelphia, AND J. $. KINGSLEY, Tufts College, College Hill, Mass. 
ASSOCIATE ance 
Dr. C: O0. WHITMAN, cago, 
ProF.. C. M. WEED, Dartam, N; 
Pror. A. C. GILL, Ith 
. BESSEY, 
Pror W. S. BAYL 
Lincoln 
Neb., C. SOS Philadel 
EY, Marve Maine, 
H. 
PROF. E. A. ANDREWS 
35 cts. per Copy. 
phia. 
S, Baltimore, 
. H. C. WARREN, Princeton. ERWIN F. cee Wia D.C 
Vol. XXX. DECEMBER, 1896. No. 360 
CONTENTS. 
PAGE PAGE — 
THE BIOLOGIC ORIGIN oF MENTAL VARIETY GENERAL NOTES. 
Herbert Nichols. 964 Petrography.—The Sioux Quartzite of Iowa 
B é —The Peridotites of North Carolina—Shales 
NEY BRANCH (D. C.) QUARRY WORKSHOP AND aid Bhites From: Walenta a Rees 
TS ImPLements. .. (Continued. ) se HOES Botany. — The Evolution of a Botanical 
trated ) Ce Wio.: 90 Journal—The North American Species of 
Fosstis AND FOSSILIZATION, niga ed. ) Physalis and Related Genera—The Nomen- 
er . P. Gratacap, 993 | clature of Mycetozoa—The Flora of Wyoming 
THE GEOGRAPHICAL DISTRIBUTION OF BATRACHIA —The Lichens of a Correction De ania 
AND REPTILIA IN NORTH AMERICA. (Con- ~ Panfhbatani PON en Wiens ses eres 
inued E. D. Cope. 1003. | = SYS: 
ener) iit 20. e Noth on "utpala On the 
Epiror’s Taste.—The Survival of Useless Goidé Giane The Food of Birds— 
Names ;—The Date of Wachsmuth and Preliminary Description 2 a New Vole from 
Springers: Crinoidea;—Dates of Issue of La brace niece New 
the Naturalist for 1895-6. . . 1027 Entomology. aA N N Vew enhy in ASI Study of 
RECENT LITERATURE-—Gregory’s Plant hhatenec} Diptera—Color Variation of a Beetle—Ameri- 
—Boulenger’s Catalogue of Snakes in the ean Nematine—Entomological Notes. . 053 
British Museum—Nuttall’s Handbook of EER cs ements of Hiestotnarea 
Birds—Education of the Central Nervous Moving pigment in Eggs—Fertilization. 1059. 
System—Lydekker on the Geographical Psychology. —The Effects of Loss of Sleep. . 1061 — 
History of Mammalia.” (Illustrated.) - 1028 | PROCEEDINGS or SCIENTIFIC SOCIETIES. . 1064" 
Recent Books AND PAMPHLETs. . 1035 | Sctentiric News. . 1068 © 
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