INDEX TO VOLUME XX. 



Academy of Sciences, Twenty-ninth 



Meeting of the Ohio, 1. 

 Additions to the Catalog of Ohio 



Vascular Plants for 1919, 131. 

 Agents in the Distribution of Fresh 



Water Sponges, 355. 

 Allies of the Ferns of Ohio, 298. 

 America, Horseflies from. Middle I, 185. 

 America, Horsefliesfrom, Middle II, 311. 

 American Tingidse, New North, 49. 

 Annual Meeting of the Ohio Academy 



of Science, 1. 

 Anthomyidae and Scatophagidag, 



Descriptions of Diptera of the 



Families, 267. 

 A Preliminary Survey of the Protozoa 



of Mirror Lake, on the Ohio State 



University Campus, 89. 

 Associates of Young Perch, 137. 



Bass Island Region, Young Perch 



of, 137. 

 Bat, The Hoary in Ohio, 35. 

 Bees and Wasps, 292. 



Caddis-worms as Agents in Distribu- 

 tion of Fresh-Water Sponges, 355. 



Catalog of Ohio Vascular Plants for 

 1919, 131. 



Caves at Put-in-Bay, Ohio, 38. 



Cerebral Ganglia, Origin of, 299. 



Cicadellidse, Generic Aflfinities and 

 Descriptions, 153. 



Corythuca Bulbosa, 17. 



Crane-flies (Tipulidas, Diptera), 193. 



Descriptions of Diptera of the Families 



Anthomyidie and Scatophagidse, 267. 

 Descriptions of Horse-flies from Middle 



America, I and II, 185, 311. 

 Descriptions of a New Genus and 



New Species of Cicadellidae, 153. 

 Descriptions of New North American 



Tingidae, 49. 

 Descriptions of New Species of 



Elachista, 167. 

 Dieciousness in Thalictrum Dasy- 



carpum, 25. 

 Diptera, Tipulidae, 193. 

 Diptera of the Families Anthomyidae 



and Scatophagidae, 267. 

 Distribution, Food and Fish Associates 



of Young Perch in the Bass Island 



Region of Lake Erie, 137. 

 Distribution of Fresh Water Sponges, 



355. 



Erie, Young Perch in the Bass Island 



Region of Lake, 137. 

 Elachista, Notes on and New Species, 



167. 

 Families of the Anthomyidae and 



Scatophygidas, 261. 

 Fauna of a Single Drop of Pond Water, 



87. 

 Fauna of Ohio, Water Striders New 



to, 205. 

 Ferns of Ohio, 298. 

 Fish Associates of Young Perch, 137. 

 Flowers of Apocynum and the Syphid 



Fly Mesogrammia, 261. 

 Food and Fish Associates of Young 



Perch, 137. 

 Food of Spiders, 215. 

 Fossil Mollusca of Ohio, 173. 

 Fresh Water Sponges, Agents in Dis- 

 tribution of, 355. 

 Generic Affinities of Certain Cicadel- 



lidas, 153. 

 Ganglia, Origin of Cerebral, 299. 

 Hairy Leaf Coverings, Relation to 



Transpiration, 55. 

 Hoary Bat in Ohio, 35. 

 Homoptera, Cicadellidae, 153. 

 Horseflies, Descriptions of, 185, 311. 

 Impatiens Pallida Forma, Speciosa 



F. Nov., 204. 

 Incurvaria, a New Genus Allied to, 24. 

 Inertia, Springs of Minimum, 320. 

 Katmai Expeditions, Results of, 267, 



292, 325. 

 Lake Erie, Young Perch in the Bass 



Island Region of, 137. 

 Landslide, the Great Mageik, 325. 

 Leaves, Resistance to Transpiration, 55. 

 Mageik Landslide, 325. 

 Marl Deposits in Ohio and their Fossil 



Mollusca, 173. 

 Meeting of the Ohio Academy of 



Science, 1. 

 Mesogramma Marginata and the Flowers 



of Apocynum, 261. 

 Microlepidoptera, a New Genus of, 24. 

 Microlepidoptera, Notes on Elachista, 



167. 

 Minimum Inertia, Springs of, 320. 

 Mollusca in Ohio, Fossil, 173. 

 New Genus Allied to Incurvaria 



(Microlepidoptera), 24. 

 New Genus of Cicadellidae, 153. 

 New North American Tingidae, 49. 



356 



