12 EIGHTEENTH REPORT. 



SECTION OF ZOOLOGY. 



W. W. Newcomb, Chairman 



Room Z 355, Natural Science Building 



Wednesday, March 29, 9:00 a. m. and 1:30 p. m. 



The Collection of Formicidae in the Museum of Zoology, University of Michigan. 



Frederick M. Gaige. 

 A Synopsis of the Tadpoles of Michigan Frogs. Helen Thonii)son Gaige. 

 A New Michigan Turtle. Alexander G. Ruthven. 

 Fo.x's List of Michigan Birds. Bradshaw H. Swales. 

 On the Number of Young in the Garter-snakes. Crystal Thompson. 

 The Birds of the Douglas Lake Region, Michigan. Norman A. Wootl. 

 A Fossil Musk Ox Skull from Michigan. E. C- Case. 

 The Rearing of Volvox in the Laboratory. George R. Larue. 

 DifTerential Mitoses in the Ovaries of a Gyrinid Beetle. C. P. Russell. 

 The Origin of Differentiation in the Fggs of Certain Insects. R. W. Hegner. 

 Periodical Zoological Literature in the Library of the L'niversity of Michigan. R. 



W. Hegner. 

 Polyembryony in a Parasitic Hymenopteron. R. W. Hegner. 

 Methods for the Collection and Preservation of Animal Parasitic Woi'ms. George 



R. liaRue. 

 The Crane FUes of the Upper Peninsula. .J. Speed Rogers. 

 A Preliminary Survey of the Fauna of Third Sister Lake. J. Speed Rogers. 

 Oxygen Favoring Male-production in Rotifers. A. FrankUn ShuU and Sonia Ladoff. 

 A Problem in Evolution. Bryant Walker. 

 The Process of Ovulation in Ampliibia. Bertram G. Smith. 

 Notes on Pleodorina californica Shaw. Bertram G. Smith. 

 Exhibit of Photographs of Michigan Animals. A. F. Combs. 

 Some Conceptions of Palaeogeography. E. C. Case. 

 The Phylogenetic Position of the American Opossum. E. D. Huntington. 

 Some Effects of Sunhght on Paramoecium. H. ]\L McCurdy. 

 The Opportunities for Zoological Work at the Biological Station of the University 



of Michigan. O. C. Glaser. 



