330 JAS. J. SIMPSON—ENTOMOLOGICAL 
on a trolley from Minna, on November 23rd and 24th. At 84 miles the line 
runs at a considerable distance from the river, but numerous G. swbmorsitans 
alighted on the natives on the trolley. No water exists anywhere in this 
vicinity, and the bush is fairly open, and gets gradually thinner, until at Minna 
there are only a few stunted trees scattered about (Plate XII, fig. 1 and text- 
fig. 1). At 982 miles there is a large river, on the banks of which the bush 
is very dense; no tsetse were seen there, but in all probability they exist ; 
while at 103 miles there is a small stream, 20 feet deep during the rains, but 
reduced to isolated pools in the dry season. There Glossina submorsitans was 
caught, and it is noteworthy that at this point one of the construction camps 
was situated, and practically every horse brought there died of trypanosomiasis. 
Dr. Morrison, who did a considerable amount of travelling on this line, writing 
to me about this region, says: ‘‘ Hippocentrum versicolor and Tabanus biguttatus 
var. croceus | have caught at Katcha station, and the former along with Tabanus 
taeniola in the van all along the line. These species enter the vans and carriages, 
and are thus carried from place to place all along the Baro-Kano Railway.” 
At Minna, blood-sucking flies of any description are seldom met with. The 
following species were, however, obtained: Hippobosca maculata, Stomoxys 
ealeitrans, Myzomyia costalis, Anopheles watsoni, Myzorhynehus paludis and 
Mansonioides uniformis; while the ticks comprised Hyalomma  aegyptium, 
Amblyomma variegatum and Rhipicephalus faleatus. Dr. Macfie informed me 
that the only Tabanid he had seen during a three months’ stay at this station 
was T. taeniola, and it is more than probable that this was carried to Minna in 
some railway vehicle. There is a large herd of Fulani catile at Minna, and 
the death rate is extremely low, which in itself gives an indication of the paucity 
of such insects as may be implicated in the transmission of disease. 
North of Minna, the country through which the railway runs is fairly open, 
with the exception of a few isolated kurimis. Near Guni, where the River Dinia 
is crossed, Haematopoa pallidipennis and a species of Tabanus, not yet identified 
and probably new, entered the van in which I was travelling, Further 
on, at Kogin Sirikin Pawa, on the river of that name, numerous //ippobosca 
maculata and Haematopota pallidipennis swarmed around the ponies, and one 
specimen of the TJ'abanus mentioned above was caught; but although I 
carefully examined about a mile of the banks of the river itself, no tsetse were 
seen, In the small pools left by the falling river were numerous mosquito ege- 
rafts, and also large numbers of both Anopheline and Culicine larvae and pupae. 
One small specimen of Tabanus, probably 7. gratus, was seen but not caught, 
At the River Kaduna, the terminus of the railway at the time of my visit 
(Pl. XITI, fig. 2), only HW. pallidipennis, T. gratus and T. pertinens were seen, 
(9) Kateri. 
Prior to my visit to Northern Nigeria, reports had been received by the 
Principal Medical Officer, Dr. 8S. W. Thompstone, C.M.G., that sleeping sickness 
was very prevalent in and around Kateri in the Zaria Province—a very inac- 
cessible region seldom visited by Europeans. At the request of Dr. Thompstone, 
I visited this district in December. A start was made from Kugo on the Baro- 
Kano Railway on November 29th ; Kateri was reached on December \st; two 
