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PACIFIC SCIENCE, Vol. VI, April, 1952 
usual marginal grasses. As at Jacquinot Bay, 
New Britain, clumps of Penmsetum macro- 
stachyum (Brongn.), Clitoria sp. (Papilion- 
aceae), and Cucumis sp. (Cucurbitaceae) were 
also commonly present. Algal mats were com- 
posed mainly of the green algae Spirogyra and 
Hormidium or the blue-greens Oscillatoria, 
Anabaena, and a member of the Chroococ- 
caceae. 
Hemipterans of the families Notonectidae, 
Gerridae, and Veliidae, a small dytiscid beetle 
of the genus Bidessus, nymphs of Odonata, 
and developmental stages of Chironomidae 
(Diptera) comprised the usual macrofauna 
associated with mosquitoes in long-estab- 
lished ground pools. There was insufficient 
time available for studying the significance 
of any of these arthropods as predators of 
developing mosquitoes. Webs of spiders be- 
longing to the genera Epeira and Carepalxis 
often spanned portions of ground pools and 
such artificial larval habitats as oil drums. On 
several occasions remains of Anopheles 
farauti and Culex annulirostris were found in 
these webs. 
NOTES ON THE BIONOMICS OF THE 
MOSQUITOES COLLECTED 
Anopheles farauti Laveran, 1902, Soc. de 
Biol., Compt. Rend. 54: 908. 
At the time of the survey there were 18 
ground pools of a semipermanent nature in 
the abandoned RNZAF area in Tangalan 
plantation. Sixteen of these pools held de- 
velopmental stages of A. farauti. Although 
many of them were exposed to direct sun- 
light and contained predaceous insects, shade 
and shelter were afforded the anophelines by 
marginal and emergent vegetation, floating 
masses of green and blue-green algae, and 
surface debris. The other two pools were 
without vegetation other than felted, bottom- 
dwelling algae. Although numerous other 
arthropods were present in these, mosquitoes 
were absent. The presence of predators to- 
gether with the lack of sheltering vegetation 
probably explained the absence of ano- 
phelines from these two pools. 
Larvae of Culex annulirostris were always 
associated with those of A. farauti in the 
ground pools examined. Estimates of the 
hydrogen-ion content of the water of these 
larval habitats made with nitrazine paper 
ranged from pW 5.5 to 7.0 and averaged 
pA 6.5. During the daytime the water tem- 
perature averaged about 33°C. and once was 
recorded as 4l°C. in an exposed situation. In 
this last case, all the larvae of both C. annuli- 
rostris and A. farauti present were sheltering 
in the shade afforded by floating coconut 
husks and an oil drum half-submerged in the 
water. The average larval population of A. 
farauti per square foot of water surface (-50 
counts) was 75, early instars outnumbering 
fully developed larvae by about five to one. 
On one occasion numerous anopheline 
larvae were found in association with those of 
C. annulirostris and Aedes quasiscutellaris in a 
44-gallon drum half-filled with water, shaded 
by the eaves of an abandoned hut. The water 
was cloudy and its hydrogen-ion content was 
6.0. Many larvae and pupae of Chiro- 
nomidae were associated with the mosquitoes. 
A. farauti was recorded from only one other 
artificial larval habitat on Nissan, when seven 
fully developed larvae and one pupa were 
found, together with 25 larvae and pupae of 
A. quasiscutellaris, in a tin can shaded by tall 
grasses and containing 300 cc. of rain water. 
Numerous adult females of A. farauti were 
captured at the camp each evening. In addi- 
tion, many specimens of both sexes were 
taken by sweeping the marginal grasses 
around larval habitats during the daytime 
with a hand net. 
Aedes (Finlaya) kochi (Donitz, 1901),Insek- 
ten-Borse 18: 38. 
Developmental stages were found in water 
held in the leaf axils of most of the taro plants 
{Colocasia sp.) examined. This water was al- 
ways clear, the hydrogen-ion content ranging 
from 6.0 to pA 7.0, and the water temper- 
