MALARIA EXPEDITION TO NIGERIA 251 
new ones are continually being made — the old ones remaining unfilled. Those in the 
neighbourhood of European quarters could, however, be easily filled up with earth 
and refuse. 
(d) The art of making good roads and footpaths seems to have been lost by 
the Europeans of the West Coast. They are made with such evident lack of 
engineering skill as to permit of the rain-water lodging in shallow puddles along their 
course, or are so badly ditched on each side that water lodges in the gutters as a series 
of small pools. These are conditions encountered in many parts of the Protectorates, 
and especially at Lokoja, in Northern Nigeria, as already referred to. Further, after 
being once constructed, the roads seldom obtain any further attention — the ditches are 
permitted to partially fill up or become overgrown with weeds. They invariably form 
excellent breeding places for Anopheles : we were always able to find numerous larvae 
in them. 
It is essential that public works and engineering departments in Nigeria should 
bestow considerably more attention to the construction of properly ' battered ' and 
' ditched ' roads and footpaths, especially in the neighbourhood of the European 
quarters — both goverment and traders — and thereby remove circumstances which are 
often a dangerous factor in conditions conducive to ill-health among Europeans in 
these districts. 
To the small hill streams again principles of drainage are applicable. In the 
hilly regions of Northern and Southern Nigeria hill streams are numerous, gorged and 
rapid during the wet season, small and sluggish in the dry. During the latter season 
they afford numerous places for the breeding of Anopheles, especially at the points 
where they are near human habitations. Here and there they swell out into shallow 
pools from which the water flows very slowly r here larvae are often found, as well 
as in the sluggish corners and back eddies of the stream. It is evident that a deepen- 
ing of the stream in parts, or a reconstruction of the channel in others, with occasional 
attention to see that the channel is clear, would annihilate the undesirable conditions. 
(<?) These conditions have been already described, and, in the places where they 
were observed by us, it was by no means difficult by judicious drainage to remedy 
them. In places where these conditions are extensive — reaching over a considerable 
area of country— drainage might prove very expensive and even impossible. 
(/) ^ e ^ a d no experience of these conditions, and as to whether they really 
occur we are not certain, having only hearsay evidence of their existence from others 
who have experienced a dry season on the River Niger. As previously stated, it is 
very possible for such conditions to arise, but actual observation is necessary to arrive 
at any decision as to their extent and how they might be treated, if at all. 
There is no doubt that thorough surface drainage in very many parts of 
Nigeria would go a long way towards preventing malarial fever among Europeans, 
