TRANSACTIONS 



OF THE 



American Philosophical Society. 



Held at Philadelphia, 



B PROMOTE TLL KNOWLEDGE. 



AW. A" . Part L 4io % pp. 6s. with 3 Plates. 



v Pub lis is 



CONTENTS. 



I. — I story of the Pelycosauria, with a Descrip- 



tion of the Genus Dimetrodon Cope. By G. 

 Baur and E. C. Ca- 



Part II. 4(0, pp. 1-4, with 5 Plates. 

 :ist Published. 



CONTENTS. 



II. — The Chronological Distribution of the Elasmo- 

 branchs. By O. P. Hay. 



III. — Results of Observation with the Zenith Telescope 

 of the Sayre Observatory from January 19, 1894, 

 to August 19, 1S95. By Charles L. Doolittle. 



IV. — A Study of the Chromosomes of the Germ Cells 

 of Metazoa. By Thomas H. Montgomery, Jr. 

 Ph.D. 



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Address THE LIBRARIAN OF THE 



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