20 
AUDY & HARRISON 
Investigation. — Mr. Ensoll and one junior assistant started collecting in this area on 
October 4. They were joined by Mr. Nadchatram on October 17, and the party remained 
until November 8. An attempt was made to collect hosts from several representative areas 
which had been selected during a preliminary inspection followed by a study of air photographs 
of the area. A senior officer paid two visits to the area and the military malaria-survey per- 
sonnel gave a considerable amount of help. Transport was provided by Malaya District HQ. 
The following table (Table 4) gives details of the collection. An attempt was made to 
recover infection from a number of larvae of T. akamushi taken from several rats ; Dr. Savoor 
reported a negative result. 
Table 4 
Details of mite-infestation at the S. Menyala F.R. area, shown as the number of infested hosts 
FOLLOWED BY THE TOTAL NUMBER OF MITES OF EACH NAMED SPECIES. 
Host species 
R. r. argentiv enter: 
from behind military Camp ... 
from proposed site 
R. r. jalorensis (mostly from 
Camp area) 
R. r. diardii 
R. exulans 
R. whiteheadi 
R. annandalei 
7 up aia glis , tree shrew ... 
Callosciurus species (20 notatus ; 
1 nigrovittatus, 1 tenuis) 
Birds : 
Hypotaenidia striata , rail 
Turnix suscitator, quail 
Excalf actoria c. chinensis, button 
quail 
* 1 ^ 
t-i <U 
<D 
£> .5 
g g 
A <L> 
E-h 
17 
6(462) 
39 
4(28) 
3(m) 
11 
9(198) 
1 
20 
3 ( h )* 
1(2) 
4 
1 
2 
22 
1 1(25) 
3 3(286)(one 
with 246) 
2 1(17) 
Co *-» 
13 <0 
s 
<ao 0 
cz> 
-s: 2 
<0 5: 
<D 
X! 
p 3 
£ 
•M 
O 
4 ( 19 ) 
2 ( 3 ) 
1(23) 
1(21) 
12(370) 
. 
E. indica 
1(2) 
W. enode 
1 ( 13 ) 
1(90) 
G. fletcheri 
11(127) 
* 10 of these vector larvae came from 2 rats in grass from the Malay Regiment Camp area. 
Islands in the Malacca Straits 
(10 days — January, 1950) 
A full account of this investigation has been published (Audy et al. 1950). A reconnais- 
sance survey of Jarak Island, which lies almost in midchannel 40 miles from the coast, was 
carried out because of an outbreak of scrub-typhus in a museum expedition there in 1932 and 
also because of reports of what appeared to be scrub-itch there. The only mammals found 
on the island were a fruit-bat (in small numbers) and an overcrowded and sickly population of 
Rattus rattus jarak (which appears to be a local feral representative of R. r. diardii). All 
the rats were infested by Trombicula deliensis (average about 200 per rat), and a number were 
also infested by Walchia rustica (attached to the chins), parasitoid mites, and worms. Ticks 
(as yet unidentified) were present but confined to the skinks which were quite common on the 
island. All appearances suggested an entirely introduced fauna and flora, i.e. of an oceanic 
rather than continental type. 
STUD. INST. MED. RES. 
