SUMMARY. The insect L. cerealium feeds on wheat and oats and on various meadow grasses in spring and summer. The method of egg‐laying, hatching, and the habits of adult and immature stages are noted and described. The total life history from the egg to adult takes 29–35 days; egg period 10–13 days, larval period 13–17 days, pre‐pupal period 2–3 days and pupal period 6–7 days. L.cerealium has been found to be responsible for non‐setting of seeds in wheat and oats. The character of the injury is described. Laboratory experiments on wheat show that in proportion to infestation the injury to ears is increased. Males have short life. The fertilised females fly off, after the crop is harvested, and hibernate in grass or other sheltered places during winter. The emergence of adult females from hibernation was about late May in 1930. This species appears to be single brooded here. In Aptinothrips rufus the method of egg‐laying, hatching, etc., is similar to L. cerealium. The two forms of this species differing in the number of antennal joints are generally found separate but occasionally mixed up in various proportions. The distribution of the two forms and the ratio collected from various localities are given with number of males, females, and immature stages. The six‐jointed form is found to contain eggs all through the year and the eight‐jointed form only for a few months of the year. The relationship of the two forms is discussed and it is suggested that there appears to be four races within the species, a sexual and a partheno‐genetic race of each form. An internal nematode parasite was found in Aptinothrips rufus. The parasite causes sterility in almost all cases. Predaceous Trombidium larvae were also found attached to A. rufus.
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U. S. Sharga (1933) studied this question.