of Edinburgh, Session 1880 - 81 . 67 
Olfactory tubercle a simple elliptical tubercle, with no visible 
markings. 
One specimen from Station 160 (South of Australia), 2600 
fathoms. 
Styela gyrosa, Heller.* 
A considerable number of specimens, many of them united into 
masses and supported by a common stalk, from Port Jackson, 6 
fathoms. 
Styela grandis , n. sp. 
External appearance . — Shape irregularly pyriform, the anterior 
end being large and somewhat globular, while the posterior narrows 
into a short thick stalk, by which the animal is attached. Ventral 
edge straight or slightly concave, dorsal long and strongly convex. 
Branchial aperture a little to the ventral edge of the anterior end, 
directed ventrally ; atrial on the dorsal edge about one-third of the 
way down, directed dorsally and slightly anteriorly ; both apertures 
sessile, and not distinctly lobed, but conspicuous. Surface irregular, 
but not rough, towards the base much corrugated transversely, the 
rest of the surface more or less seamed and wrinkled. Colour dirty- 
white, becoming slightly darker towards the base. Length, 9 -5 cm. ; 
breadth, 6 cm. 
Test thin and soft, but fairly strong. 
Mantle very delicate ; closely united to the inner surface of the 
test. Musculature consisting chiefly of a number of fine bundles 
of fibres running longitudinally. 
Branchial sac with four folds on each side, the most dorsal one on 
each side placed very close to the dorsal lamina. There are three 
internal longitudinal bars on each side of a fold, and about six in 
the interspace. The alternate transverse vessels are wider than the 
intermediate ones. The meshes are immensely elongated trans- 
versely, and contain each about twenty stigmata. 
Dorscd lamina rather wide and perfectly plain, having no ribs or 
teeth. 
* C. Heller, Untersuchungen liber die Tunicaten des Adriatischen und 
Mittehneeres, iii, Abth. p. 15, 1877. 
