A new species of leafhopper, Draeculacephala robinsoni, very similar to D. portola Ball, has been examined and found to be distinct from that species, on the bases of internal male genitalia and vertex angle.

The cage and pot described here were used successfully in extensive studies on the transmission of aster yellows virus by the six spotted leafhopper, Macrosteles fascifrons (Stål) (Richardson 1966). The use of this composite unit results in a saving of labour, cost, and greenhouse space.

The materials for the testing unit consist of a round peat pot, 3 in. in diameter and 3 in. deep, and a 1-lb polyethylene bag approximately 8 in. long, with an opening 3 in. in diameter. The seedling growing in the pot is covered by the inverted bag and the mouth of the bag is then pulled down over the rim of the pot and secured with a rubber band (Fig. 1). Several hundred small holes are made in the bag to permit air exchange.

Ecological studies, undertaken to determine the fluctuations of phytophagous mites and predators in apple orchards, were conducted in 1955, 1956, and 1957 at Rougemont, Que., in two plots sprayed only with fungicides for the control of apple scab, Venturia inaequalis (Cke) Wint., and in a third one sprayed, in addition to fungicides, with all insecticides needed for the control of destructive insects. Phytophagous mites were more numerous in the plot sprayed with insecticides than in plots sprayed only with fungicides, and densities of the mites in the latter plots were inversely proportional to densities of predators. A similar relationship existed in the insecticide plot between the amount of chemicals used and numbers of predators present. The principal mite predators were Typhlodromus rhenanus (Oudms.), most effective against the two-spotted spider mite, Tetranychus urticae Koch, and Mediolata mali (Ewing), most effective against the European red mite, Panonychus ulmi (Koch).