1042 Charles Paul Alexander 



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Weyenbergii, H. Beitrage ziir Anatomie und Histologic der Hemi- 

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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 

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



Williston, Samuel W. Manual of the families and genera of North 

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Manual of North American Diptera, 3d ed., p. 1^05. (Refer- 

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

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EXPLANATION OF ABBREVIATIONS USED ON PLATES 



A=antenna Pl^pleuron 



C=cardo PM = prementum 



Lb=l;ibium, or labial lobes S = stipes 



Momentum SM = submentum 



Aid = mandible Sp = spiracle 



Mx = maxilla St = sternite 



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, 1021. 



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

 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. 



Alemoir 37, A Modified Babcock Method for Delermininij Fat in Butter, the next preceding number in this 

 scries of jiublications, was mailed on December 10, 1920. 



