192 
They lie rather deep in the genital chamber and 
are visible only from end view or when the 
genitalia are tilted back (as in Fig. 2b). The 
dististyli are heavily sclerotized on their inner 
margins and appear to serve as supporting 
structures for the aedeagus; each has a small 
point at upper edge of the apex. 
Length: Body, 5. 0-7.0 mm.; wings, 6.0- 
8.0 mm. 
female: Antennae 11 -segmented, counting 
the small tip. The front is raised in the middle 
into a prominent ridge which extends from 
the ocelli to the antennae; this ridge is de- 
veloped into a strong tubercle just before the 
antennae. The front and face are brownish- 
black in ground color and densely grayish 
pubescent; the tubercle at the lower part of 
the front is yellowish in color. The wings are 
darker brown fumose than in the male. 
Length: Body, 7. 0-9. 5 mm.; wings, 10.0- 
12.0 mm. 
The species has been found to be quite 
variable in size. Edwards said that it is smaller 
than fulvicollis and the wing of his type was 
recorded as 5.0 mm. 
type locality: Aru Islands. 
Type in the British Museum (Natural 
History). 
I have studied the type and numerous speci- 
mens from many localities in New Guinea 
(Netherlands, Papua, and Northeast), Aru, 
and Burn islands. 
Plecia bakeri Malloch 
Fig. 3 a, b 
Plecia bakeri Malloch, 1928, Linn. Soc. N. S. 
Wales, Proc. 53(5): 605. 
Fitting in the fulvicollis complex because of 
the all rufous thorax and readily differentiated 
from all known Plecia by the genital characters 
of the male. The ninth sternum is produced on 
posterior median margin into a pair of slender 
lobes separated by a narrow V-shaped cleft. 
The claspers are rather slender, pointed, and 
curved inward, they extend about two-thirds 
their length beyond the apex of the sternum 
PACIFIC SCIENCE, Vol. XII, July, 1958 
Fig. 3. Plecia bakeri Malloch. a , Ninth sterum; b , 
ninth tergum. 
(Fig. 3 a). The ninth tergum is divided into 
two plates by a deep V-shaped cleft on the 
hind margin (Fig. 3 b). 
Length: Body and wings, 6.0-7. 5 mm. 
Described from Baguio, Benquet, Philip- 
pine Islands. I have seen specimens from 
several localities on Luzon, Los Banos, Bataan, 
Pampanga, and Mindanao, Philippine Islands. 
Type in the U. S. National Museum. 
Plecia borneensis Edwards 
Plecia borneensis Edwards, 1931, Jour. Fed. 
Malay States Mus. 16: 489, fig. 1. 
A small species whose genitalia closely re- 
semble those of P. aruensis Edwards. It is dif- 
ferentiated by having the pleura dark; the 
male with but six segments in the antennal 
