318 
THE VOYAGE OE H.M.S. CHALLENGER. 
Coelocormus^ n. gen. 
Colony massive but not attached ; deeply concave on the upper surface, so as to 
contain a large central cavity. 
Ascidiozooids large, not distinctly divided into regions ; branchial aperture five- 
lobed. 
Test soft and gelatinous. Test cells numerous and large, No bladder cells. 
Calcareous spicules present in the superficial layer. 
Branchial Sac large. Stigmata very long and narrow. 
Dorsal Lamina represented by a series of long triangular languets. 
Tentacles well developed. 
Alimentary Canal extending beyond the branchial sac posteriorly, but not 
forming a distinct abdomen. Stomach smooth-walled. 
Reproductive Organs not large. Ovary only presentin the adult Ascidiozooid. 
Testis formed of a number of spermatic vesicles. Vas deferens spirally coiled. 
The essential characters and relationships of this very remarkable genus have been 
already discussed under the definition of the family.' It contains the single species 
Coelocormus huxleyi, which was obtained in the South Atlantic, off the east coast of 
Patagonia. 
Coelocormus huxleyi, n. sp, (PI, XXXVII, figs. 1-8 ; PL XXXVIII. figs. 1-4). 
The Colony has the form of a kidney-shaped mass, with a large internal cavity 
opening to the exterior at one end. It shows no sign of having been attached. The 
surface is fairly smooth. The colour is a light grey. 
The length is 3‘5 cm., the greatest breadth is 2 cm., and the thickness is 1‘5 cm. 
The Ascidiozooids are large and fairly numerous. They are distributed evenly over 
the whole surface of the colony, and are not arranged in any definite systems. No 
common cloacal apertures are visible externally. The body of the Ascidiozooid is placed 
vertically in the colony, and is not distinctly divided into regions. The branchial 
apertures are conspicuous. 
The Test is soft and flexible. It is of a light grey colour and is semi-transparent 
throughout. The matrix is in the main clear and structureless, but contains a few long 
delicate fibres which traverse it in all directions. The test cells are large and numerous, 
but not conspicuous. No bladder cells are present. Calcareous spicules are present in 
the outer layer of the colony, but they are not very abundant. They are stellate and 
fairly regular, but vary in size and in the thickness of the rays and the sharpness of their 
points 
^ xo/'^oj and x,o^(*6g. 
