110 



JOURNAL OF ECONOMIC ENT0:M0L0GY 



[Vol. & 



WEBKESDAY 



Fig, 8. — Charts showiog the moisture and temperature control in the breeding 

 chamber from December 21 to 9.00 o'clock December 26, 1914, compared with the 

 humidity and temperature in the insectary and outdoors. T, temperature; H, 

 humidity. 



Note. — The temperature during the night of December 25 was ten degrees below 

 zero. This air was brought directly into the spray chamber and in less than three 

 seconds was passed into the breeding chamber at a temperature indicated- by the 

 chart. 



Lettering for Plate 2. 

 K, suction fan; L, spiro steam turbine; P, air compressor; T, tempering or heating 

 chamber; U, graduated thermostat; V, diaphragm steam valve; W, steam line; 

 Y, air duct leading from heating chamber to the breeding chamber; Z, automatic 

 lubricator. 



