^ TABLE OF CONTENTS VII 



Article 



Marshall, William B. New land and fresh-water mollusks 

 from Central and South America. No. 2638, pp. 1-12. 

 November 6, 1926 ^ 12 



New species: Odontostomus (Cyclodontina) clmseae, 0. (C) 

 iheringi, Succinea feUpponei, Ampullaria superba, Nephronaia^ 

 lempensis, EUiptio divaricatus, Tetraplodon linki, Hyria ivheat- 

 leyi, Diplodon aswicionis, D. {Cyclomua) sniithi, Aiwdontites 

 irisans. 



MuESEBECK, C. F. W. A revision of the parasitic wasps of 

 the subfamily Braconinae occurring in America north of 

 Mexico. No. 2642, pp. 1-73. March 17, 1927 ^ 16 



New species: Bracon crassifemur, Agathirsia testacea, Crassomv- 

 crodus nigrithorax, C. apicipennis, Bassus marginatifrons, B. 

 fioridanus, B. abdominalis, B. rufofemoratus, B. spiracularis, 

 B. bakeri, B. crassicornis, B. difflcilis, B. tenuiceps, B. tvinanae, 

 B. laticeps, B. brevicornis, B. caUfomicus. 



. Descriptions of new reared parasitic Hymen- 



optera and some notes on synonymy. No. 2633, pp. 1-18. 

 October 15, 1926 ^ 7 



New species : Microhracon helianthi, Meteorus tetralophae, M. 

 cingiliae, Apanteles pterophori, A. noctuidiphagus, A. ammalonis, 

 A. gordU, A. pyrophilae, A. teleae, A. coxalis, A. hadenae, A. 

 cerurae, A. lyciae, Microigaster scopelosomae. 



Ross, Clarence S. The optical properties and chemical com- 

 position of glauconite. No. 2628, pp. 1-15. May 29, 1926 ^_ 2 



Shannon, Raymond C. Review of the American Xylotine 

 Syrphid-flies. No. 2635., pp. 1-52. December 1, 1926 * 9 



New genera : Xylotomvma, Xylotodes, Philippimyia, Tatuomyia, 

 Crepidomyia. 



New species : Tropidia pygmaea, Planes vnlUstoni, P. rondanU, P. 

 schildi, Xylotomima dubia, Xylotodes brevipilosus, X. sacajaweai, 

 Xylota confusa, X. viridaenea, X. rainieri, X. argoi, Planes, 

 boliviensis, P. minor Sterphus aurifrons, Crepidomyia tri<yrepis, 

 Tatuomyia batesi. 



New varieties. Xylotomima nemorum americana, Xyloia naknek 

 atlantica. 



, . The Chrysotoxine Syrphid-flies. No. 2637, 



pp. 1-20. November 26, 1926 ^ 11 



New species : Chrysotoxum, Chinook, C. aztec, C. radiosum, C. lada- 

 kense, C. chinense, C. nigrifacies, C. tartar, C. tuberculatum, C. 

 fratellum, C. mongol, G. draco, C. caeleste. 



New subgenus : Primochrysotoxum. 



, . {See also Harrison G. Dyar) 10 



^ Date of publication. 



