1921.] The Eighth Indian Science Congress. CCX xt 
Dysentery also a Panay has been noticed. Omitting. po deaths due 
to Cholera and injury the total mortality me for the pre-water-works 
period was 36°14 laverigs of ten BR haely ) while the rate for the period after 
the — of water-supply is 24:42 (ave hed of five years) which means 
a reduction of 11°72 per 1000 on the general death rate apart from Cholera 
and inju nw 
The following conclusions are dra 
(1) That — mortality in abigh towns of Bengal is mostly water- 
bor at any rate can be reduced considerably by the 
provision of an abundant pure water-supp 
(2) a in gk case of oe rie of Hooghly, Chinsurab, ar e one 
ath from Choler s been avoided as a re t of the 
age 
aperlt tio ina a ka genes Fite: wo 
other causes have ieee avoided as well. 
Studies in town water-supplies.—By V. Govinpa RaJv. 
It is an enquiry into the methods of hae chape tae of water employed 
in Eanual towns. It is pointed out that in the smaller water works the 
methods of ae aes adopted bring Sine ery little improvement in 
the bacterial co of waters and hence it is claimed that the money 
adopted in European countries are unsuited to India as here ee 
Sneaitions are generally on a lower level ye preclude the carrying ou 
of efficient and up-to ae te schemes. It is therefore necessary that tices 
should be an investigation as the cuit bility of various nates of 
water purification ~ different “Tovaliitie In tropical climates storage 
brings about a part geld rem tee improvement in the bacterial 
contents of polluted waters consequently for small communities tank 
s’ storag ex 
to be provided. e relative advantages and disadvantages of slow sand 
and mechanical ines for these localities must be caraally rong ag In 
a arg 
t e not y 
satisfactory results. Slow sand filters have given excellent results on a 
aoe rat but in the case of the smaller plants the results have not been 
isfactory. This however is believed to be due to faulty design. 
New thoracic apper pogo in anopheline larvae.-—By 
M. O TIRUNARAYANA IYENGAR. 
and. »3 
are not known nor their homology. A nine Re ry 
appendages, 1 
stephenst, minimus, ¢ wlivijacies. fuliginosus, 4 
author has also found these appendages in the saree at A, maculipennia 
and bifurcatus from England. 
