RESEARCH IN BRITISH WEST AFRICA. 345 
come from? When we take into consideration the small number of horses which 
are brought to this province annually, and the extremely short interval which 
elapses before these show symptoms of trypanosomiasis and die, we must 
conclude that, whatever be the carrier, the percentage infected must be large. 
It seems hardly possible that the infection could be carried, in the circumstances 
quoted, from horse to horse, but if this be so the infected insect must remain 
infective for a very long time. More probable, however, is the hypothesis that 
the insects become infective from some other source, such as game, but as this 
has been neither proved nor disproved it opens up a fruitful line of research. 
V. RECORDS OF BLOOD-SUCKING INSECTS AND OTHER 
ARTHROPODS FROM NORTHERN NIGERIA. 
The majority of the insects mentioned in the following list have already been 
referred to in the preceding pages, but it might be well to tabulate these for the 
sake of completeress. The table will also form a guide to any who may be 
interested in this work and serve to show what species may be expected, but it 
must be borne in mind that in all probability this list is very far from complete, 
especially as regards the more northerly parts of the Protectorate. 
In the majority of the species the records are far too scanty to admit of any 
discussion of their distribution, so that I propose to leave this over until more 
data are forthcoming. I may also add that several new species from Northern 
Nigeria await description and these have not been included in the following list. 
Order DIPTERA. 
Family CuLIcIDAE. 
Section Anophelina. 
Anopheles wellcomei, Theo. Myzorhynchus mauritianus, Gr. 
Myzomyia costalis, Loew. | a paludis, Theo. 
funesta, Giles. Nyssorhynchus maculipalpis, Giles. 
umbrosa, Theo. | pharoensis, Theo. 
marshalli, Theo. squamosus, Theo. 
flavicosta, Edw. | watsoni, Edw. 
Section Culicina. 
Aedomyia catasticta, Knab. Trichorhynchus (Culiciomyia) nebulosus, 
Banksinella luteolateralis, Theo. Theo. 
Culea decens, Theo. Ludlowia mimomyiaformis, Newst. 
,, duttoni, Theo. Mansonioides uniformis, Theo. 
, fatigans, Wied. Mucidus mucidus, Theo. 
4 grahami, Theo. Reedomyia biannulata, Theo. 
4, guiarti, Blanch. Stegomyia africana, Theo. 
- invidiosus, Theo. a fasciata, Theo. 
., quasigelidus, Theo. | FA acheleinensis, Theo. 
,, _tigripes, Gr. var. fusca, Theo. 5 sugens, Theo. 
.. univittatus, Theo. Taeniorhynchus cristatus, Theo. 
Toxorhynchites brevipalpis, Theo. 
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