CONTENTS. 



For Announcements, Reports, etc., see General Index. 



PAGE 



BoDiNE, Joseph Hall. Experimental results in Ischnura and 



Enallagma 103 



Cadwalader, John. Legal attainments of Doctor Dixon 116 



Calvert, Philip P. Eruptions of the Costa Rican Volcano 



Irazuin 1917-18 73 



Carroll, Mitchel, The hind-gut, abdominal tracheae and 

 rectal respiration in the larva of Mecistogaster modes- 

 tus from Costa Rica 86 



CoNKLiN, Edwin Grant. In memoriam, Samuel Gibson 



Dixon, M.D., LL.D., Sc.D 115 



Cullen, Anna M. Rectal tracheation of Argia putrida 75 



CuLLEN, Anna M., Janet P. Jamieson, Mitchel Carroll, 

 and Joseph Hall Bodine. The rectal tracheation and 

 rectal respiration of the larvae of Odonata zygoptera 75 



Fowler, Henry W. New and little-known fishes from the 



Philippine Islands 2 



A new Characin from Paraguay. 141 



In memory of Samuel Gibson Dixon, M.D., LL.D., Sc.D 115 



Jamieson, Janet P. The tracheal supply of the rectum of 

 the larvae of Argia talamanca from Juan Vinas, Costa 

 Rica 81 



Jordan, David Starr. Notes on Gistel's Genera of Fishes 335 



New Genera of Fishes 341 



PiLSBRY, Henry A. On the generic position of Sonorella 



wolcottiana Bartsch 139 



Pilsbry, Henry A. and James H. Ferriss. Mollusca of the 

 southwestern States — IX. The Santa Catalina, Rin- 

 con, Tortillita and Galiuro Mountains — X. The 

 mountains of the Gila headwaters. Plates III-VII 282 



Rehn, James A. G. On a collection of Orthoptera from the 



State of Pard, Brazil (Plates I, II) 144 



RoYER, B. Franklin. Dr. Dixon's work in sanitary science 127 



Stone, WiTMER. Dr. Dixon's life and services to the Academy 120 

 Birds of the Panama Canal Zone, with special reference to 

 a collection made by Mr. Lindsey L. Jewel 239 



Vanatta, E. G. Two new shells from Hayti 237 



Wade, Bruce. New generic names for Upper Cretaceous 



Gastropoda...... 114 



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