1915.] | A. OKA : The Tunicata of the Indian Museum. 27 
The Tentacles are simple and filiform, and about sixty in number. ‘They are of 
various sizes, some very long, and are arranged apparently without any regularity. 
The Branchial Sac extends to the base of the mantle and is not longitudinally 
plicated. The transverse vessels are all narrow. The internal longitudinal bars are 
very numerous and bear pointed conical papillae at the angles of the meshes. There 
are no intermediate papillae. The meshes are elongated antero-posteriorly and each 
contain two stigmata (Pl. V, fig. 4). Parastigmatic vessels are not present. 
The Dorsal Tubercle is horseshoe-shaped, broader than long, with the aperture 
directed forwards. 
~The Dorsal Lamina is a rather broad membrane, showing ribs which are con- 
tinued beyond the margin of the lamina as long tentacle-like filaments (PI. V, fig. 5). 
The Alimentary Canal forms a close loop on the left side of the posterior half of 
the body. The stomach is ovate, smooth-walled, and is not sharply bounded from 
the intestine. The anal aperture is not toothed. 
The Gonads are placed in the narrow space between the first and second loop of 
the intestine, as well as over its branchial surface. The testicular follicles are seen to 
be connected by delicate ducts with the vas deferens. The oviduct is distended by 
a large number of spherical ova and is quite conspicuous; it runs along the terminal 
portion of the intestine. 
Locality.—Off Cape Negrais, Burma, at Station 387, 15° 25’ N., 93° 45’ E.; 
depth 40-49 fathoms; bottom sand and coral; November 16th, 1909. 
This specimen presents in external appearance much resemblance to Ascıdıa 
depressiuscula, Heller, with which it also shows certain affinities in internal structure. 
The shape and colour of the body, the mode of attachment and the condition of 
the test are much the same; and in the number of tentacles, the shape and size of 
the alimentary canal, and the position of the gonads our specimen agrees pretty well 
with the description of that species given by Herdman in his report on the Tunicata 
of the Gulf of Manaar. But the number of stigmata in each mesh of the branchial 
sac is in A. depressiuscula five or six instead of two, and the dorsal lamina is a plain 
membrane with slight ribs and small marginal denticulations, differing in a marked 
degree from what is found in our specimen. 
Ascidia andamanensis, n. sp. 
(Pl. V, figs. 6-9.) 
External Appearance.—The body is longish oval, much depressed laterally, and 
is attached by the whole of the left side (Pl. V, fig. 6). The branchial aperture is 
anterior, terminal, and appears to be sessile; the atrial, on the other hand, is placed 
on a prominent cylindrical siphon springing from the dorsal edge about half way 
from the anterior to the posterior end. The apertures are eight-lobed and six-lobed 
respectively, as usual. The surface is quite naked and smooth except for a few 
slight longitudinal creases and is of a pale yellowish-grey colour. The size of the 
body is about 32 mm. in length and 16 mm. across the wider posterior part of the 
body ; the length of the atrial siphon is 6 mm. 
