. Animal parasites and human disease. Insects as carriers of disease; Medical parasitology. Fig. 230. pygium o f tsetse fly. Alcock.) Hypo- mouthparts when the latter are not in use. and it is thus the palpi alone that are seen when the long blunt-tippcnl proboscis is ob- served. The characteristic form of the antenna? is shown in Fig. 229. The thorax is relatively large and quadrangular, with a characteristic pattern which is, however, inconspicuous in some species. The abdomen may be nearly uniform dark brown, or pale brown banded with a dusky color. The male has a large oval swell- ing on t
. Animal parasites and human disease. Insects as carriers of disease; Medical parasitology. Fig. 230. pygium o f tsetse fly. Alcock.) Hypo- mouthparts when the latter are not in use. and it is thus the palpi alone that are seen when the long blunt-tippcnl proboscis is ob- served. The characteristic form of the antenna? is shown in Fig. 229. The thorax is relatively large and quadrangular, with a characteristic pattern which is, however, inconspicuous in some species. The abdomen may be nearly uniform dark brown, or pale brown banded with a dusky color. The male has a large oval swell- ing on the under side of the last segment of male tlie abdomen, the " hypopygium " (Fig. 230), (After which forms a good distinguishing mark be- tween the sexes. Distribution, Habits, etc. — Tsetse flies, fortunately, are lim- ited in their distribution to the middle portion of the African continent from south of the Sahara Desert to the northern l)orders of British South Africa (Fig. 231,^). One species occurs in the southwestern corner of Arabia. Tsetses are by no means evenly distributed over this great area, but are limited locally to "fly-belts," chiefly along rivers and at the edges of lakes. Ail {he factors which cause the " patchy " distribution of tsetses are not known; there are cases where close limita- tion to certain areas cannot be explained l)y any known refjuirements of the flies. Different species vary in their choice of habitats; ( palpalifi (Fig. 230), the carrier of C»aml)iaii and Nigerian seldom fouml more than 30 vards from. Fu 231. flies. \\\ /// Approxiiimti' r:iiitxis of taetse (Conipiled from Austen.) raiiKf of entire genus gloaaina range of o- morsitunx range of g. /x/// Icepmg sickness, is the edge of water where a sandy bottom and overiiangiiig vegetation is al)im- dant, though it follows animals and man for a few liundrcd yanls from such positions. This species is found oiilx' in Please note that th
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectmedical, bookyear1918
