316 Report of the Department of Entomology. 



brass curtain rings proved very satisfactory. Thin circular cover 

 glasses, the same as used in microscopical work, were placed 

 over the rings and held in place by paraffin. Enough paraffin 

 was always used to entirely cover the ring. Tio admit air small 

 holes were made with the point of a fine needle, through the 

 paraffin, just under the cQver glass. Pla'te LII, Fig. 2. 



In our studies sound apples were found very convenient. A 

 single female could be isolated and her offspring easily counted, 

 or a single larva could be kept within narrow limits for close 

 observation. 



