64 Proceedings of the Royal Society 
Mantle reddish-brown, moderately thick, closely united to the 
test. 
Branchial sac with four folds on each side. There is a con- 
siderable space on each side between the endostyle and the ventral 
fold. Internal longitudinal bars extremely numerous and much 
crumpled. Meshes small, elongated vertically, containing each one 
or two stigmata, and divided horizontally. 
Dorsal lamina in the form of languets. 
One specimen from Station 160 (South of Australia); 2600 
fathoms. 
Sty da Jiava, n. sp. 
External appearance. — Shape rudely spherical, slightly elongated 
laterally; anterior end convex. Attached by the posterior end and 
half of each side to a piece of coral ; dorsal and ventral edges free 
and rounded. Apertures sessile, 4-lobed, moderately far apart, at 
the opposite ends of the anterior extremity. Surface of the test 
flat, but minutely scaly ; scales largest and most distinctly marked 
round the apertures. Colour light yellow, with a brownish tinge at 
the apertures ; white on the area of attachment. Length (antero- 
posterior), 1 ’6 cm. ; breadth (from side to side), 2 '4 cm. ; thickness 
(dorso-ventral), 2 cm. 
Test thin, but very tough, opaque ; white and glistening on the 
inner surface. 
Mantle rather thin. Muscular bands numerous, but very fine. 
Branchial sac with four folds on each side ; folds very slight, being 
merely the approximation of a number of internal longitudinal bars. 
There are about ten at these places, and ten in the intermediate 
opener parts. Meshes square or elongated vertically, containing 
each four stigmata, and divided by a narrow horizontal membrane. 
Endostyle conspicuous, rather wide, reddish-brown. 
Dorsal lamina ribbed transversely, and slightly toothed at the 
edge. 
Tentacles simple; three sizes — fifteen large, fifteen small, and 
about thirty very minute ones. 
Olfactory tubercle , placed at the bottom (posterior extremity) of 
a rather deep peritubercular area ; small and irregular in shape. 
