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Proceedings of the Eoyal Society of Edinburgh. [Sess. 
Fig. 11. — Calyptophylliim ohvolvatum, n. sp. Solen- 
omerite of the right gonapod from the inside. 
(Same lettering as in fig. 10.) 
Fig. 12. — Calyptopliyllum integrum, n. sp. Base of 
the 2nd pair of legs (P2), with the right vulvar 
invagination {i. ), anterior view. L, Tracheal stalks ; 
s., sternite ; c., coxal joint. 
not fused with the posterior median plate, 
Sternite of second pair of 
legs very much as in the 
male obvolvatum, but not as 
broad {s., fig. 12) ; the tracheal 
stalks (t.) do not stand so 
wide apart, they are long, 
bent in usual way, with an 
inconspicuous internal uncus 
about the middle. Coxae (c.) 
more slender proximally, thus 
appearing widened apically. 
Vulvar invaginations (k, 
fig. 12) distant from each 
other, not deep enough to 
conceal entirely the vulvae. 
Vulvae strongly chitinised, at 
least twice as high as long. 
When at rest, the operculum 
is turned forwards, the mound 
facing backwards. The oper- 
culum is a subquadrate piece, 
by one - fourth lower than 
the mound, with the apical 
margin shallowly excised and 
with the outer angle more 
produced than the inner (fig. 
13). The surface shows two 
parallel, thickened ridges 
bearing macrochaetse. When 
the vulva is closed, the an- 
terior margin of the valves 
of the mound are pressed 
tight against these ridges, 
concealing the lateral margins 
of the operculum. 
The mound (fig. 14) is 
asymmetrical ; the outer half 
is more developed than the 
inner half. Valves narrow, 
tipped with hyaline rounded 
