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YoRKE (Warrington) & Blacklock (B.). Notes on the Bionomics of 

 Glossina palqxdis in Sierra Leone, with special Reference to its 

 Pupal Habitats. — Ann. Trap. Med. Parasit., Liverpool, ix, no. 3, 

 July 31st 1915, pp. 349-362, 7 plates, 1 map. 



The observations here recorded were made on the Cape Lighthouse 

 Peninsula at the mouth of the Sierra Leone River, wliich is a pear- 

 shaped piece of land about 3 miles long, 1| miles broad at its base, 

 and about three-quarters of a square mile in area, its seaward end, 

 for two-thirds of the whole length, being barely 100 yards wide. The 

 Aberdeen creek, which separates it from the mainland, is fringed by a 

 dense growth of mangroves, in some places half a mile broad. Oil 

 palms are found all over the peninsula with a dense undergrowth of 

 young palms and these, though other trees are present, constitute 

 the principal vegetation. Glossina pal pedis is to be found in fair 

 numbers all over the area at the beginning of the dry season, 

 December to January, and cases of sleeping sickness have occurred 

 in the vicinity. The chief object of the investigation was the study 

 of the pupal stage of the fly, and in the first place examined, the 

 hollow trunk of a baobab, 18 empty pupal cases were found under 

 dead leaves lying on a fine dry gravel or within half an inch of the 

 surface. The tree was ICO yards from the sea and not less than 450 

 yards from the nearest fresh water. Pupal cases were only found 

 within a foot of the trunk and not in the centre of the floor of the 

 cavity. A number of other likely places were searched, but without 

 success, only two cases being found, one at the base of a palm tree close 

 to the sandy shore and one at the base of a similar tree in dense bush. 

 A systematic search was then made round the base of oil palms, trunks 

 of which are difficult of approach, because of the dense barrier, 3 feet 

 wide, formed by the lower petioles which completely shade the ground. 

 On removing dead leaves and debris, 20 empty pupal cases were found, 

 nearly all on the surface of the gravelly soil and about a foot from the 

 trunk ; the deeper layer of soil contained very few cases. By careful 

 examination of the soil round many palms, large numbers were found, 

 10 to 20 under one tree being common and in two cases about 75 were 

 collected. In only one instance was a puparhim found in the earth 

 in the angle between the petiole and the trunk. Puparia were very 

 rarely discovered under other trees, the shade apparently being 

 insufficient. The authors summarise the results of their observations 

 as follows : — The breeding grounds of G. palpalis are not so strictly 

 Kmited to the immediate vicinity of water as has hitherto bee i thought ; 

 they may occur quite independently of fresh water and at least a 

 quarter of a mile from sea- water. Although G. palpalis is to be found 

 in considerable numbers in mangrove swamps and may travel in these 

 to a distance of at least half a mile from dry land, the swamps do not 

 constitute a breeding ground of the fly. The pupae of G. palpalis 

 do not hatch when subjected to daily flotation in sea- water. The 

 ground round the trunk of oil-palms [Elaeis ifmneensis), which have 

 not been stripped of their lower petioles, constitutes an excellent 

 breeding place for G. palpalis, which can breed in localities in which 

 this is practically the only tree. Stripping the oil-palms of the lower 

 petioles would suffice to destroy the breeding ground in such places. 

 (C216) Wt.P.12/91. 1500. 11.15. B.&F.Ltd. Gp. 11/3. A 



