Near Belleville, Ontario, it was necessary to take quantitative samples of predators in shallow pools in field studies of the natural control of mosquitoes. To expedite this work a light-weight sampling cage was constructed. Its description follows.

The cage (Fig. 1, top) consists of an enclosure (A) and two sorting trays (B and C). The enclosure, covering one-half square metre, is of four screened frames, each 12 inches high. Each frame is of aluminum extrusions (Higgins-Homeshield Limited, Toronto, Ontario) of the types shown in details F and G. The extended flange on extrusion G, used at the right-hand side of each frame, provides a means of overlapping and fastening at the comers of the enclosure. After the frames are fastened together to form a square, pointed angle-aluminum legs (D) 16 inches long are fastened to each inside corner. Small braces are alio fastened across each corner to hold the enclosure in shape.