CONTENTS 



VOLUME IX 



No. 1. BiRGE, E. A. and Juday, Chancey. A liuiiiologieal 

 reconnaissance of West Okoboji. 



No. 2. Stoner, Dayton. Nesting habits of the hermit thrush 

 in northern ^lichigan. 



No. 3. Trowbridge, A. C. The erosional history of the drift- 

 less area. 



No. 4. Lindsey, a. W. The Hesperioidea of America north of 

 Mexico. 



No. 5. Clark, A. H., Rathbun, Mary J., Boone, Pearl L., 

 Shoemaker, C. R., Clark, H. L. Reports on the 

 Crinoids, Ophiurans, Brachyura, Tanidacea and Iso- 

 poda, Amphipods, and Echinoidea of the Barbados- 

 Antigna expedition of 1918, 



