STUDIES ON APHIDES INFESTING THE POTATO CROP

S ummary1 This communication is the substance of a report on a survey of the aphis population in certain districts of Scotland carried out from 24 July to 4 August 1936. 2 Forty‐three centres in eastern Scotland, from Midlothian in the south to Ross‐shire in the north, were examined by the standard method for determining the aphis “index” figure. 3 The varying figures obtained have been analysed with a view to establishing any relation there might be with ( a ) proximity to winter host plants, and ( b ) meteorological conditions such as temperature, humidity and wind velocity. 4 The results have been summarized in a discussion in which are indicated the special precautions necessary to ensure health in seed‐potato stocks.