846 
THE TROPICAL AGRICULTURIST. 
[June 1, 1905. 
graphical and physical conditions of the 
Dutch City are in many respects nearly 
similar to those of the African town, 
Amsterdam has three different sources to 
fujni&h it with water for domestic and 
general purposes — well-water, river-water and 
water from the sand dunes. It is from 
latter that the principal supply of potable 
water is obtained, and it was the 
hope that the sand dunes of the Lagos 
coast might be similarly utilised for the 
requirements of Lagos that brought Sir 
Wm. Macgregor to Holland. The visit is 
likely to be very fruitful in good, and to 
improve much the hygienic conditions of 
the West Coast Capital. Fever is the scourge 
which is most dreaded on the West African 
Coast, and the Lagos Governor has thrown 
himself heart and soul into the Mahial 
Campaign. One dees not require to read 
between the lines of his report, to notice 
how earnest he is that while the anopheles 
mosquito may be reduced if not exterminated, 
nothing that can otherwise be done for the 
improved sanitary conditions of his pro- 
vince should be omitted or overlooked. In 
Holland since the introduction of the 
" dune " water, the mortality from typhoid 
has been reduced from 1910 per 1,000 in- 
habitants of 40 years ago, to 0-215 of 1880 
to 1889, the latest statistics quoted ; while 
Malaria all but disappeai-ed through the 
destruction of thelarvre of the mosquito by the 
introduction of sea water into the canals for 
flushing purposes. Temperature, as well as 
the salinity of tlie water, has much to do 
with the increase of mosquitoes ; and as 
the heat at Lagos has a very much higher 
range than it obtains at Amsterdam, the 
results noted there will hardly be a safe 
guide for the African tropical town. The 
destructive action of salt-water on the 
mosquito larvae is a more liopeful subject ; 
but the minimum degree of salinity suffi- 
cient to arrest the development of the 
mosquito larvae, has yet to be determined. 
And in this connection its deltrmination 
has its own importance for Colombo — if 
the " fly " nuisance of our own inland 
sheet of water is only to be remedied by 
turning the latter into a semi-salfcwater lake. 
Appended to Sir Wm. Macgregor's report is 
an interesting paper on " Malaria in Holland," 
by Dr. H. J. M. Schoo of Krommonie. Dr. 
Schoo's experience in some respects runs 
counter to the opinion of other experts — 
for while he traces malaria to the puncture 
of the anopheles, he denies the protecting 
quality of quinine, which other authorities 
recommend to be taken when in feverish 
localities. He had for many years 
kept his district free of malaria by the long 
and liberal use of the drug, but the fever 
had re-appeared in an epidemic form, and 
he had not found that his people were 
less aflected than in other places where but 
little quinine was[ uted, and only for short 
periods. ,, I cannot, therefore, believe," he 
says " in the prophylactic influence that 
Koch attributes to quinine," It is, however, 
a comfort to know that although quinine 
may not prevent malaria it can cure it, and 
acts like a poison on the blood parasites 
which appear with the malady, especially 
on the gametes of which the blood is full. 
Dr. Schoo says •' a single dose of sulphate of 
quinine, arrests completely the development 
of the gametes." The cause o^ the Dutch 
malarial epidemic, which broke out after 
some twenty years of immunity is a puzzle 
to explain, and Dr. Schoo is inclined to find 
one of the latent centres in the soldiers and 
others who had returned to Holland from 
the over-sea colonies with malaria in their 
systems. This is, apparently, the " unknown 
factor " in the communication of malaria re- 
ferred to in oar colunms but a day or two 
ago. The centre of the Malarial Ciim- 
paign is in Lagos, and although Sir Wm. 
Macgregor may not be the head of it, he is 
certainly the heart and soul of the enter- 
prise, and displays all the energy and skill 
of a successful and sympathetic leader. All 
over the world where the dread fever has its 
haunts, the Lagos influence is felt, and if the 
African West Coast Governor had done 
nothing else to deserve grateful recogni- 
tion, the impulse he has given to this branch 
of scientific research entitles him to the 
honour of having secured one of those famous 
victories of Peace, which are no less re- 
nowned than those of war. 
„ « . 
STUMP ROT IN TEA AND COFFEE. 
INDIAN ORYPXOGAMIST'S LETTKR. 
The following is the letter by Dr. E J Butler, 
Cryptogamic Botanist to the Government of 
India, on " Stump Rot and its Treatment," 
which was read after Mr Graham Anderson's 
memo, on the same subject at the recent 
meeting of the South Mysore Planters* Asso- 
ciation :— 
This history of the ordinary cases of sturap rot 
a? I have seen it oa one Coffee estate in Coorg and 
on numerous Tea gardens in Assam and Dehra 
(there being little doubt from what I have seen that 
the Tea and Coifee diseases are for all practical 
purposes identical) is as follows : — 
A shade tree is cub down or more commonly 
" ringed " and the stump left to rot in the ground. 
Some time afterwards, it may be in a few weeks or 
periiaps not for 18 months or more, the tea or 
cofi'ee bushes next adjacent to the site of the stump 
begin to wither and die off. Then a circle further 
out dies, and year by year the circle grows. On 
exposing the roots, the old stump is seen to have 
undergone a peculiar rot which results in a condi- 
tion by which the outer layers become converted 
into a soft mass of earth and bark in which whitish 
cobweb-Jike patches can be seen here and there. 
This rot, which usually begins at the base of the 
tree stump, extends out along the main roots to 
where these adjoin the roots of a tea or coffee 
biisli. These latter take the rot, and if they are 
dug out before quite dead, it will be noticed tiiat 
a knife can be driven in quite easily for an inch 
or so into the bark of the "collar," wiih which 
enrth and white patches are found intermingled 
just as on the tree stump. Having once aUaeked 
Che coffee roots the rob can pass from root to rook 
even across a few inches of earth and can appar- 
ently extend indefinitely. The cause of the 
diseae is a fungus which has been identified at 
Kew as Eosellinia radiciperda(M.asaee), Though 
