560 Mr. D. Sharp and Mr. F. Muir on the Comparative 
ture on the apex of the internal sac differs in details (Pl. LX XII 
figs. 200, 200a). 
D. lidens and D. semicuprea. 
Aedeagus very like D. comari, but the armature on the sac is 
totally different (Pl. LX XIII, figs. 201 and 202). 
D. lemnae. 
Has the cap long and thin. The armature on sac is distinct from 
those described above (Pl. LX. XIII fig. 203). 
Carpophagus banksiae (Pl. LX XIIT figs. 204, 2047). 
Median lobe large, chitinous, tubular and curved; the median 
orifice at apex, the median foramen occupying the ventral basal half. 
Tegmen forming aring-piece, with a very longlobe as cap. Internal 
sac large with complex armature at apex (204a) consisting of a pair 
of complex side lobes (c) and a slender median process (6) through 
which the ejaculatory duct passes and opens on its apex. 
Mecynodera balyi. 
Median lobe well chitinised, curved and fairly short, forming a 
flattish tube; the ventral edge of the median orifice projecting 
beyond the dorsal edge: median foramen large, occupying the 
ventral portion of the basal half. Tegmen forming a ring-piece, 
with large cap apically deeply divided and furcate ; the median strut 
or keel on the ventral aspect, of median size. Internal sac not 
extending through the median foramen. Armature at apex of sac 
consisting of a slender median process on which the ejaculatory duct 
opens, two chitinous plates embedded in the membrane below the 
median process, and a Y-piece above also embedded in the membrane. 
Polyoptilus sp. 
This is very like Mecynodera but the cap is less furcate at the 
tip. 
Diaphanops westermanni. 
This is very like Polyoptilus sp.?; the cap is differently shaped, 
being broader distally and bearing there a small emargination ; the 
armature at the apex of the internal sac (P]. LXXITI fig. 205) con- 
sists of a slender process on which the ejaculatory duct opens (a) 
protected by a stronger and broader process above it (), a broad plate 
(c) grooved along the centre supports the membrane below and 
another and smaller plate (d) supports the membrane above. N.B.— 
In the figure, (d) and its pointing line are imperfect. 
