[ 45 ] 
)r deposit their dejecta. The reduction of the number of mosquitoes even 
)f apparently harmless species is, therefore, of considerable importance. 
Organisms corresponding to Shiga and Flexners B. dysentericus were 
solated^in many cases of dysentery from the intestinal contents, the ulcers 
and the scrapings from these ulcers. They were not found m the spleen 01 
lymphatic glands even when enlarged, or in the Hepatic abscesses. 
Dysentery is of rare occurrence in Europeans residing m the largei 
centres, but is common amongst those who do much travelling. Amongst 
natives resident in the towns it is fairly common, but more so m the small 
mines and in the bush. Gaol dysentery does not occur here but m Singa¬ 
pore gaol epidemics of severe type of dysentery do occur. It occurs at all 
ao-es, but proportionally is more common from 25 to 35 than at other decades. 
The water supply to European houses m Kwala Lumpur is from t le 
Ampang Reservoir entirely. To the native quarters it is m part only from 
this source, more often from surface wells or even holes in the ground 01 
from polluted rivers and streams. Milk is often mixed with water from 
! such sources. . . . . , , • , 
With dysentery there is not the same certainty that it is only derived 
from previous cases as in typhoid. On the contrary the evidence of 
travellers through uninhabited tracts of country strongly supports the wide 
spread belief that jungle streams are a fruitful source of the disease. 1 his 
question will be further considered in dealing with the bacteriology o 
natural water supplies. 1r , 
Dysentery was the cause of 17 or rather more than half the cases 
examined amongst the Tamils. The same types of Dysentery were found. 
In two cases there were Hepatic abscesses. 
This greater liability to deaths from Dysentery on the part of the 
Tamils is, I believe, racial, but it must also be remembered that the Tamils 
are more careless as to the water they drink and the disposal 01 faeces. 
Note. —Experiments were made by placing various larvae in water to whicn cultrues 
of various organisms were added and allowing them to develope m such ;^ e / n 
food material and other organisms were present m the water but the P^tence ? p 
added was determined from time to time by plating^ B. pyocyaneous B. prodW°sus, ■ 
violaceous, Sarcina lutea and B. subtilis were the organisms used Shortly before 
pupation the larvae were transferred to sterile water and after pupation changed frequent y 
to different tubes of sterile water to remove as far as possible adherent organisms. 
The mosquitoes as soon as possible after hatching were transferred to slope agar tubes 
and retransferred to other sterile tubes either dry or containing agar agar, and f.naily were 
allowed to die on sterile broth or were dissected on agar plates and these were then 
incubated a^-vre experimented with were those of Culex fatigans, Stegomyia scutellaris and 
fasciata and Anopheles Rossii. The results obtained differed with each species of mosquito^ 
Stegomyia fasciata in every instance was found to carry B. pyocyaneous some ot the tubes 
giving pure cultures of that organism. In none of the other mosquitoes used was this 
organism found. B. violaceous was found in none of the tubes used by th ® m ^ s 4 u,t ° es ' 
B. prodigiosus only exceptionally, and B. subtilis in about | of the tubes. Sarcina lutea 
was carried by Culex fatigans in a few instances only Moulds of various kinds 
common with all, but most abundant with Stegomyia scuttellans . _ 
Mosquitoes caught in various districts were examined m a similar manner, 
specimens Stegomyia fasciata were found with B pyocyaneous, and one specimen 
Wyeomyia splendens, a pure bamboo breeder, also harboured this organis • 
specimens of Culex fatigans. Anopheles Rossii and Desvoidea fuscus an organism reser ? b ^ 
Coli but not coagulating milk was found. This organism appears to be closely related 
to the water organisms of this class so common in Malaya. Experiment i\i > 
typhosus failed in every instance. Organisms, therefore, may be acquired as larvae: fr 
sewage or other sources and conveyed by the adult mosquitoes to water, fruit, sugar or 
any other substance. 
