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PUBLIC RECORD OFFICE
C.O.
Reference :-
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expected to find G. palpalis common at fords, cross-roads, and at the entrances to towns and villages, and this I found to be the case in Ashanti.
I have been unable to make out a belt distribution for G. palpalis in any part of the country visited. No doubt the number found in different places varied within very wide limits, and in a few places the fly was apparently absent. In such places, however, I have always succeeded, by careful search, in finding one or more speci- mens. To do so it has sometimes been necessary to pitch the tent and to remain a day, and, on a few occasions, it was only upon a return visit that the fly was found. On a return visit fly was sometimes found to he numerous upon a road or in a village where not a single specimen could be found a week before. No place, therefore, should be pronounced free from G. palpalis until after many careful examinations, made at different hours and at different seasons of the year.
It should be remembered that all my work upon this road was done during, or at the end of, the wet season, when water was plentiful everywhere, and that, therefore, no true estimate of the relation between the presence of water and the presence of the fly could be formed. A true estimate could only be made by exam- ining the road during both the wet and the dry seasons, and this was not possible. When apparently absent I have succeeded in finding specimens, either on the road at the entrance to the village, under the shade trees in the village, or upon the path leading to the village water source. This path should always be examined when fly is scarce, for along this path the women and children pass to and fro, or sit gossiping all day long.
Pupa.
Pupa-I had not the good fortune to find any pupæ dropped under natural surroundings, but several pupe were dropped in my glass-bottomed collecting boxes. Here the female fly, having dropped the pupa, at once turned round so as to face it and laid her proboscis upon it, remaining quite motionless in this position for a considerable time. I was unable to perceive any exudation from the proboscis. Of course this position was assumed by the fly under very unnatural conditions, and may not be assumed under natural ones, but it occurred to me that pupæ might conceivably be infected with trypanosomes by the mother in such a manner. Pupe thus dropped in boxes are somewhat smaller than normal, and usually do not develop into imagines.
G. fusca (Walker).
(2) On the Cape Coast road this species was found only at Fumsu. This town is situated on the River Fum and is the site of a Government rest-house.
My tent was pitched near the rest-house and not far from the river ford. Here a specimen of G. fusca entered my tent at 5.45 p.m., and a second specimen was caught at the ford four days later (18th December, 1907) upon my return journey. Here, as elsewhere, G. fusca was associated with G. palpalis, the latter species being
very numerous.
G. pallicera (Bigot).
(3) A single specimen of G. pallicera was caught in the bush behind the cook- house of the Prahsu Government rest-house (16th December, 1907) at about 4 p.m.
The Cross Roads.
Two cross-roads connecting the railroad with the Cape Coast road were care- fully examined for fly:-
1. The cross-road which leaves the railroad north of Akrokerri at 137 miles and, running almost due east, joins the Cape Coast road near Dompoasi. This road was examined in September, 1907. G. palpalis was found to be distributed along its whole length. No other species of Glossing was observed.
2. The cross-road which leaves Obuasi and, running in a north-easterly direc- tion, joins the Cape Coast road near Brafo-Yedru. This road was examined in December, 1907.
G. palpalis was found, one and three-quarter hours' journey beyond Obuasi, on a tributary of the Jym River, and thence along the whole length of the road. No other species of Glossina was observed.
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Native Name.
The blood-sucking habit of the genus Glossina is well-known to the natives of Ashanti. Apparently there is only a generic name, and the different species are not distinguished.
The natives in Southern and Central Ashanti call the fly Ahúria (Ah-hóo-ree-ab).
Summary.
1. Three species of Glossina were found :-
(a) G. palpalis (R. Desv.), male and female.
(b) G. fusca (Walker), male and female.
(c) G. pallicera (Bigot), male and female.
2. G. palpalis was abundant and widely distributed. 3. G. fusca was relatively rare, found singly or in pairs, and always associated with G. palpalis.
4. G. pallicera was very localized and not associated with the two other species.
5. No belt distribution could be made out for G. palpalis during the wet
season.
6. G. palpalis frequents the mainroads and bush paths, most frequently found on the ground, more rarely under leaves. Attacks man by preference. Absent from the roadway in the early morning, appears about 10 a.m., or when the sun appears. Prevails until sunset. Does not appear to be attracted by artificial light. Enters the railway carriages, villages, houses, tents, &c.
7. G. fusca. Found occasionally on the main roads and bush-paths, seldom
on the ground, usually under leaves. Absent in early morning. Prevails till sunset. Not attracted by artificial light. Enters railway carriages.
8. G. pallicera. Found in bush-paths, not on the ground, but on upper sur face of leaves. Absent in early morning. Does not enter railway carriages. Very localized.
9. All three species enjoy sunshine and are most prevalent during its con- tinuance.
10. No seasonal predominance of the sexes observed during the wet season. 11. The association of G. palpalis with Stomoxys inornata (Grünberg) remark- able. The presence of one could be relied upon to indicate that of the other.
12. The Gold Coast Government Railway supplies a very efficient means of disseminating G. palpalis and G. fusca. (Recommendations.)
13. G. palpalis is chiefly associated with man and seems to frequent the roads at the same hours as do men.
14. The genus is well known to the Ashantis under the name Ahúria. Species not distinguished.
15. Ashanti natives do not attribute any importance to the bite of the fly, ie., it is unpleasant but not dangerous.
16.
G. palpalis and G. fusca found in Sekondi.
17. A fly region said to exist 12 miles outside Accra.
railway there.
18. Fords usually infested, reasons for this.
Possible effect of new
19. Crocodiles numerous at Prahsu and on River Ankobra, near Axim, and
probably at Dunkwa, on the River Ofin.
20. Difficulty of being certain that any locality is free from fly.
21. Attitude assumed by female G. palpališ after dropping pupa. bility of thus infecting pupà with trypanosomata.
DIPTERA.
Possi-
To identify or describe the numerous species of diptera collected would require at least a year's work at the subject. I propose, therefore, to limit this report to a list of those families of which specimens were found, and to treat in detail only those genera whore blood-sucking or parasitic habits render them dangerous or destruc- tive.