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EXPLANATION OF ABBREVIATIONS USED ON PLATES 
A=antenna Pl=pleuron 
C=cardo PM=prementum 
Lb=labium, or labial lobes S=stipes 
M=mentum SM=submentum 
Md=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 maiied 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. 
