No. 55.— 1904.] ANNUAL REPORT. 
157 
to quiet and kill its unwelcome little guest by depositing round it 
layer after layer of nacre, or mother-of-pearl, and when this effort 
is successful tibe result is a pearl. But when the effort is unsuccessful, 
the parasite lives on happily in the tissue of its mussel-host until a 
trigger-fish come along. Now the trigger-fish devours the mussel, 
shells and all, and in so doing devours also the living pearl- parasite 
within the mussel. But the parasite, nothing daunted, finds a new 
and congenial home in the trigger-fish, until a sting-ray in turn 
devours the trigger-fish. Even then the pearl-parasite.accommodates 
itself to yet another home, and, once more in the form of an adult tape- 
worm, hangs on with hooks and suckers to the intestines of the ray ; 
thence it again detaches its egg-laden joints and the whole cycle recom- 
mences. Having discovered the life-history of the pearl and pearl- 
mussel, the men of science are now trying to revolutionize the methods 
of pearl fishing which have been in vogue since, I believe, 323 B.C. The 
diving dress has been tried with great success, and now we are trying 
a system of dredging which is going on side by side with the old 
system of skin diving, and is, I believe, destined eventually to super- 
sede the old-fashioned methods, to the great pecuniary advantage of 
the Colony. 
Besides this we have arrived at a critical point, being almost within 
reach of a process which will enable us to wash the pearl oyster, 
instead of allowing it to rot as has been done since time immemorial 
and then muddling about in the festering mess and picking out the 
pearls by rule of thumb. We hope soon to wash the pearl from the 
oyster just as grains of gold are washed from alluvial gravel. We 
shall not get entirely rid of the rotting process, but we shall only have 
to use it to a very small extent. 
I take this opportunity of recording my experience that Ceylon 
owes a great deal to some of its Civil Servants for their very ready 
and able assistance to the scientific men. For one example I know, a? 
no one else could know, that much as we are indebted to Mr. Hornell 
for bringing about the somewhat unexpected but welcome Pearl Fishery 
of 1904, we are equally indebted in the same matter to Mr. Denham, 
the Assistant Grovernment Agent of Mannar, without whose thoroughly 
practical help the fact that there were pearl oysters to fish this year 
would never have been known to us. 
This by no means exhausts the list of scientific works in the Colony. 
A small Marine Biological Institute has been established at Galle 
under the able direction of Mr. Hornell, but the work is only in its 
infancy, and the Institute has to be closed whenever Mr. Hornell is 
away on scientific investigation. I hope that it may lead to the 
remunerative cultivation of sponges, which are found in considerable 
quantities on the coasts of the Island, but are never utilized 
commercially. 
Yery little work has been done here in geology, and work in 
mineralogy is practically only just starting with the appointment of 
Mr. Coomaraswamy to conduct a survey of the mineralogical condi- 
tions of the Colony, a task which will, of course, entail years of labour. 
Meteorology is well looked after by Mr. H. O. Barnard. There has 
been considerable talk about the establishment of a seismological 
observatory. Seismological instruments have been imported by the 
Government, but have lain idle for many years, the delay in the 
erection of the observatory being due to the fact that before the 
Island starts a seismological observatory a great many other things 
