1042 CHARLES PAUL ALEXANDER 



WESTWOOD, J. 0. An introduction to the modern classification of 

 insects 2:1-587, +1-158. (Reference on p. 512-514.) 1840. 



WEYENBERGH, H. Beitrage zur Anatomic und Histologie der Hemi- 

 cephalen Dipteren-Larven, p. 1-62. 1872. 



WHITE, P. B. The food of the common mole. Bd. Agr. London. Journ. 

 no. 5:21:401-407. 1914. 



WILLIAMSON,. E. B. Directions for collecting and preserving specimens 

 of dragonflies for museum purposes. Univ. Michigan, Mus. Zool. 

 Misc. pub. no. 1:5-15. 1916. 



WILLISTON, SAMUEL W. Manual of the families and genera of North 

 American Diptera, 2d ed., p. 1-167. (Reference on p. 29-31.) 1896. 



Manual of North American Diptera, 3d ed., p. 1-405. (Refer- 

 ence on p. 81-86.) 1908. 



WINNERTZ, J. Beitrag zu einer Monographic der Gallmiicken. Linnaea 

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WULP, F. M. VAN DER. Jets betreffende de entwikkeling van een tweetal 

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ZELLER, P. C. Dipterologische Beitrage. Part 2. En beskrifning af 

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ZETTERSTEDT, JOHANN WILHELM. Diptera Scandinaviae disposita et 

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EXPLANATION OF ABBREVIATIONS USED ON PLATES 



A = antenna PI = pleuron 



C = cardo PM = prementum 



Lb=labium, or labial lobes S = stipes 



M = men turn SM = submentum 



Md = mandible Sp = spiracle 



MX = maxilla St = stern ite 



P = palpus, or palpal sheath T = tergite 



Memoir 34, An Economic Study of Farm Layout, the fourth preceding number in this series of publica- 

 tions, was mailed on January 31, 1921. 



Memoir 35, Some Effects of Potassium Salts on Soils, the third preceding number in this series of publica- 

 tions, was mailed on January 29, 1921. 



Memoir 36, Resistance of the Roots of Some Fruit Species to Low Temperature, the second preceding number 

 in this series of publications, was mailed on January 19, 1921. 



Memoir 37, A Modified Babcock Method for Determining Fat in Butter, the next preceding number in this 

 series of publications, was mailed on December 10, 1920. 



