168 
Psyche 
[June 
membrane and bears, on its ventrolateral surface, two small smooth 
areas (Fig. 25, SA; Fig. 32, arrows) which probably represent the 
points at which the cells of the scolophore attach internally. The 
rest of its surface is covered with small rounded projections, similar 
to those observed in Hesperocorixa, which give it a granular ap- 
pearance, and it has a pattern of pentagonally or hexagonally 
arranged grooves (Fig. 32). This pattern, along with the attach- 
ment of the scolophore, suggests that the entire structure is ho- 
mologous with the base of the club-shaped body of Hesperocorixa. 
Diaprepocoris appears to possess no counterpart of the flask- 
shaped body or of the shaft and tip of the club-shaped body of 
Hesperocorixa. 
Micronecta, however, shows a possible homologue of the flask- 
shaped body. In the posterodorsal part of the sensory membrane 
lies a roughly spherical structure (Fig. 26, FL?; Fig. 31) whose sur- 
face has a granular appearance but no hexagonal pattern. Its 
position suggests that it is the counterpart of the flask-shaped body 
of Hesperocorixa. Posteroventral to it lies a larger, bulb-shaped 
body (SC) which attaches to the sensory membrane by means of a 
narrow neck. The bulb-shaped body has a hexagonal pattern, 
and is probably homologous with the spherical body of Diaprepo- 
coris (Fig. 25, SC) and with the base of the club-shaped body of 
Hesperocorixa. The grooves between the hexagons are deeper 
than those on the apparently homologous structures, and the sur- 
face of the bulb-shaped body is smooth rather than covered with 
granular projections. There is no distinctive feature to mark the 
attachment of the scolophore. 
H. Discussion 
I. Mode of Respiration 
The presence of air-bubble respiration in the subfamily Corixinae 
has been demonstrated by numerous physiological and behavioral 
studies which were mentioned in a previous publicatnn (Parsons 
1970). Similar data are lacking, however, for the Diaprepocorinae 
and Micronectinae except for a brief note concerning Micronecta 
sp. (Leong 1961). The following discussion of respiration in Dia- 
prepocoris and Micronecta is therefore based almost entirely upon 
the morphology of preserved specimens and has yet to be confirmed 
or disproved by experimental evidence. 
