The increased importance which the European red mite (Paratetranychus pilosus (Can. et Fanz.)) (= Metatetranychus ulmi (Koch)) has assumed in recent years has led to an intensive study of its biology and natural history. In the course of these investigations many workers, and in particular those in Nova Scotia (vide Lord, 1949), have become convinced that this pest can be controlled, on apple trees at least, by natural means and that some of the most active agents in its eradication are the representatives of that group of predaceous mites which Vitzthum (1941) placed in the subfamily Phytoseiinae Ber'lese, 1916 1). As the late Dr. A. C. Oudemans of Arnhem included many if not most of these species in the genus Typhlodromus as he conceived it, this paper... |