Bees oe oo eS 
OF THE 
HELD AT Palace 
FOR PROMOTING USEFUL KNOWLEDGE. 
in XX, New Series. sto, pp. 397, with Oe Plates. : 
Fust tlhe aie 
CONTENTS. | fis 2 
Art. 1.—The History of the Pelycosauria, with a De 
. tion of the Genus Dimetrodon Cope. By 
Baur and E. C. Cass. 
Art. II.—The Chronological ick batiod of fae Elasm 
branchs. By O. P. Hay. | 
Art. III. —Results of Observation ith the Zenith Telescop | s 
to August 19, 1895. By eens aap Doouritt , 
Art. IV.—A Study of the Chromosomes of the Germ Ce 
of Metazoa. By Tuomas H. Moutoomeny r 
Ph.D. 
Art. V.—Fossil Mammalia of the White River Beds Oo! 
Montana. By Ear Doverass. 
Art. VL —Results of Observation with the Zenith Teles , 
ME ies 27, 1893. seh CHARLES Le Doou 
‘SUBSCRIPTION—FIVE DOLLARS PER VOLUME. 
SEPARATE PARTS ARENOT SOLD. 
Address THE LIBRARIAN OF THE 
AMERICAN PHILOSOPHICAL SOCIETY , 
No. 104 SOUTH FIFTH STREET, Be 
