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THE EGG PARASITES 01^ THE COFFEE BUG {ANTESTIA 

 LINEATICOLLIS, STAL) IN KENYA COLONY. 



By F. W. Dry, M.Sc, 

 Recently Assistant Government Entomologist, Kenya Colony. 



I. Introduction. 



Some account of work on the egg-parasites of the coffee bug in Kenya Colony 

 has already been published in a bulletin of the Department of Agriculture of that 

 country.* 



When that bulletin was written the two common species of egg-parasites had 

 not been identified, and they were consequently referred to simply as " Species A, 

 Brown Parasite," and " Species B, Black Parasite." These two species both proved 

 to be new and have since been described by Dodd.f " X" as Hadronotits antestiae, 

 and " B " as Telenomtis truncativentris. They may be roughly distinguished as 

 follows :— 



Hadvonotiis. Abdomen brown, head and thorax black in the female ; head, 

 thorax, and abdomen black in the male ; black colour dull ; antennae in both 

 sexes of 13 segments. 

 Telenomiis. Head, thorax, and abdomen bright glossy black in both sexes ; 

 abdomen of a different type from that of Hadronotus ; antenna of the female 

 12-segmented and comparatively short and clubbed, antenna of the male 

 13-segmented, comparatively long and moniliform. 

 It is now possible to give some additional facts, but it should be made clear that 

 the investigation is in a very incomplete state. This account, put together upon the 

 present writer's ceasing to work in Kenya Colony, is a short summary of what has 

 so far been ascertained. 



II. The Life-history of the Coffee Bug. 



A full account of the life-history of the coffee bug is given by Mr. Anderson. 

 The following facts, the chief ones about the life-cycle that have a bearing on the 

 relation between the bug and its egg-parasites, are taken from his bulletin. 



The egg stage and all the instars of the nymphal stage were passed through 

 considerably faster in hot than in cool weather. The length of the egg stage varied 

 from about 9 days in the hotter months to about 13 days in the cooler ones. The 

 average length of the nymphal stage was, for the hotter months, about 75 days, 

 for the colder, 115 days. Combining egg and nymphal periods, the average times 

 from egg-laying to the nymph becoming adult were respectively 84 days and 128 days. 

 The average adult life for both sexes was a httle over 100 days, but the length of 

 life was frequently much longer, the maximum found for a female being 290 days, 

 that for a male 249 days. The average number of eggs laid during the lifetime of 

 a female was 126, but the number was often very much more, 485 being the highest 

 obtained. 



The egg of the coffee bug, as Mr. Anderson describes it, " is dull white in colour, 

 covered with a fine powder which easily rubs off, leaving the egg clear and glistening. 

 This powder appears in the form of a delicate reticulation. The egg measures 

 roughly f mm. by 1 mm. The measurement of 100 eggs, taken at random, gave 



* Anderson, T. J.— The Coffee Bug.— B.E.A. Dept. of Agric, Div. of Ent.. Bull, i, 1919. 

 t Dodd, A. P. Notes on the Exotic Proctotrupoidea in the British and Oxford University 

 Museums. — Trans. Ent. Soc. Lend., Jan. 1920. 



