Index to Volume XX 



357 



New Species of Cicadellidas, 153. 

 New Species of Elachista, 167. 

 North American Tingidag, New, 49. 

 Note on Proliferative Power of Pinus, 21. 

 Notes on Corythuca Bulbosa, 17. 

 Notes on Elachista, with Descrip- 

 tions of New Species (Microlepi- 



doptera), 167. 

 Notes on the Generic Affinities of 



Certain Cicadellidae (Homoptera), 



With Descriptions of a New Genus 



and Two New Species, 153. 

 Notes on the Genus Platycotis, 209. 

 Ohio Academy of Science, 1. 

 Ohio, Ferns and Fern Allies of, 298. 

 Ohio, Marl Deposits and Fossil Mol- 



lusca in, 173. 

 Ohio, Origin of the Caves at Put-in- 



Bay, 38. 

 Ohio, Polemoniaceae of, 43. 

 Ohio State University Campus, Protozoa 



of Lake on, 89. 

 Ohio, the Hoary Bat in, 35. 

 Ohio Vascular Plants for 1919, 131. 

 Ohio, Water Striders New to the 



Fauna of, 205. 

 Origin of Cerebral Ganglia, 299. 

 Origin of the Caves at Put-in-Bay, 



Ohio, 38. 

 Pinus, Proliferative Power of, 21. 

 Plants, Ohio Vascular for 1919, 131. 

 Platycotis, Notes on the Genus, 209. 

 Polemoniaceae of Ohio, 43. 

 Pond Water, Fauna of a Single Drop 



of, 87. 

 Preliminary Survey of Protozoa of 



Mirror Lake, 89. 

 Proliferative Power of Pinus, 21. 

 Protozoa of Mirror Lake, 89. 

 Put-in-Bay, Ohio, Origin of Caves 



at, 38. 

 Quantitative Studies in the Food of 



Spiders, 215. 

 Relation of Hairy Leaf Coverings to 



the Resistance of Leaves to Trans- 

 piration, 55. 

 Remarkable Fauna of a Single Drop 



of Pond Water, 87. 



Report of the Twenty-ninth Annual 



Meeting of the Ohio Academy of 



Science, 1. 

 Resistance of Leaves to Transpiration, 



55. 

 Results of the Katmai Expedition, 267,. 



292, 325. 

 Scatophagidae, Diptera of the, 267. 

 Science, Ohio Academy of, 1. 

 Scientific Results of the Katmai Expedi- 

 tions, 267, 292, 325. 

 Single Drop of Pond Water, Fauna of, 



87. 

 Spiders, Studies in the Food of, 215. 

 Sponges, Caddis-worms as Agents in 



Distribution of Fresh-Water, 355. 

 Studies in the Food of Spiders, 215. 

 Survey of the Ferns and Fern Allies of 



Ohio, 298. 

 Survey of the Protozoa of Mirror Lake, 



89. 

 Syrphid Fly, Mesogramma, and the 



Flowers of Apocynum, 261. 

 Thalictum Dasycarpum, Dieciousness 



in, 25. 

 The Great Mageik Landslide, 325. 

 The Hoary Bat in Ohio, 35. 

 The Origin of the Caves at Put-in-Bay,. 



Ohio, .38. 

 The Origin of the Cerebral Ganglia, 299. 

 The Relation of Hairy Leaf Coverings 



to the Resistance of Leaves to Trans- 

 piration, 55. 

 The Syrphid Fly, Mesogramma Margi- 



nata, and the Flowers of Apocynum, 



261. 

 Tingidse, New North American, 49. 

 Tipulidse, Diptera, Crane-flies, 193. 

 Transpiration, Relation of Hairy Leaf 



Coverings to. 55. 

 Twenty-ninth Annual Meeting of the 



Ohio Academy of Science, 1. 

 Vascular Plants of Ohio for 1919, 131. 

 Wasps, Bees and, 292. 

 Water, Fauna of a Drop of Pond, 87. 

 Water Striders New to the Fauna of 



Ohio, including the Descriptions of 



a New Species, 205. 



