8 PROCEEDINGS OF THE NATIONAL MUSEUM VOL, 125 
mosis. Male genitalia: eighth sternum elongate, tapering, tip slightly 
bifid; ninth sternum flattened, scooplike, tip bifid; lateral arms of 
tenth tergum rectangular, with a sharp apicomesal tooth; lateral 
process of aedeagus with a curled apical spine; aedeagus with dorso- 
mesal lobe, basal complex, narrow neck, and greatly enlarged apex. 
Female genitalia: eighth sternum with rounded ventrolateral lobes; 
internal plate rectangular in ventral view with a circular mesal 
opening, apically with a smaller ventral plate, a long internal whip 
attached to apex. 
Larva.—Length to 4 mm. Sclerites brown, head yellowish around 
eyes. Prosternum with a pair of broad plates filling the venter. Meso- 
and metasterna with narrow sclerites along posterior margins. All 
legs very similar; mid- and hindlegs with ventroapical seta of tibia 
nonfimbriate. Abdominal segments 1-6 with 1 pair, segments 7-8 
with 2 pairs of dorsal setae; segments 1-8 with a lateral seta; segment 
1 with 2 pairs, segments 2-9 with 1 pair of ventral setae. Ninth tergite 
with 2 pairs of long setae. Anal claw with 3 pairs of accessory teeth. 
Pupa.—Length 3 mm. Mandibles and labrum as in figures 5, 9. Face 
with 3 pairs of setae. Abdomen with hook-plates anteriorly on seg- 
ments 2-8 (2 and 8 lightly sclerotized and may be lacking), posteriorly 
on 4. 
Case.—Length 4 mm, width 2 mm. Made of small sand grains 
in typical shape. Irregular respiratory openings dorsally at anterior 
and posterior ends. 
MateriIAL.—Holotype, pharate male: Dominica, Morne Nicholls, 9 Nov. 
1964, P. J. Spangler, USNM Type 69879. Allotype, female: Fond Figues, 6 Apr. 
1964, O.S. Flint, Jr. Paratypes: same data as holotype, 1 2 ; same data as allotype, 
19; Clarke Hall, 11-20 Feb. 1965, W. W Wirth, 19. Other: same data as 
holotype, 7 larvae, 1 prepupa, 6 pupae; Laudat, 20 Nov. 1964, P. J. Spangler, 
1 larva. 
Brotocy.—This species has been encountered only a few times on 
the island of Dominica. The larvae were found in clear, forested 
streams about 5 yards wide, where they were attached to gravel and 
rocks on the bottom. 
Family PHILopoTaMIDAE 
The philopotamids are nearly ubiquitous wherever there is flowing 
water in most of the regions of the world. Many of the genera, in- 
cluding Wormaldia, are more or less limited to the cooler, spring-fed 
streams in mountainous regions, whereas others, especially Chimarra, 
are more diverse in the regions of larger, warmer, but still rapidly 
flowing, lowland rivers. 
The larvae construct long, tubular, silken shelters attached to the 
underside of a rock or stick, where the flow of water will keep the 
