144 MARINE BIOLOGY OF THE SUDANESE RED SEA. 
the opercular attachments are some distance from the border, but they are 
known in S. sanguinea, Norm., S. Harmsworth, Waters, S. auriculata, Hass., 
S. serratimargo, Hincks, S. arrogata, Waters, S. linearis, Hass. 
S. unicornis, J., is one of the most abundant species in the northern 
hemisphere, and it was also very abundant throughout the whole of the 
Tertiaries, and therefore it is not surprising that it is subject to considerable 
variation. It has not been mentioned from Australia, but Mr. Hincks records 
it from 8. Africa. 
There are about 18 tentacles, and frequently in large pieces no ovicells are 
seen. It is frequently darkly pigmented. From the floating stage in Suez 
docks, which “ has been afloat several years,” there are pieces 1-2 em. thick 
composed of many layers, and from Cape Verde Island there is a piece about 
0:7 mm. thick, and about 17 em.x 14cm. They are not, however, formed of 
simply superimposed layers, but of superimposed zocecia, so that the lateral distal 
walls are continuous throughout the whole thickness. This regularity is a great 
surprise, and I hope to deal with it when I describe the Cape Verde collection ; 
however, I may state that Schizoporella viridis, Thornely, which also grows in 
solid pieces, has no such continuous growth, and in section the zocecia are 
seen to be one over another, alternately like tiles ; also in Cellepora there 1s 
considerable irregularity. In some solid growths of Bryozoa the layers are 
almost independent ; however, in multilayered Melicertilidee the cells occur 
in a definite position one over the other, in a way which surprised me when 
I made the sections*. The question now raised is a very large one, of 
some paleontological interest, but it has been recognised too late for full 
examination in this paper. 
Loc. Greenland, Scandinavia, British, Atlantic, Cape Verde Islands, Medi- 
terranean, Indian Ocean, Japan, Loyalty Islands, South Africa (//inck's). 
From Suez Docks (13) (15), Suez Canal entrance (14), ship ‘ Fayoum,’ Suez 
(20), Agig Suraya (21), Cape Verde Island (2) (3), Zanzibar from bottom of 
s.s. ‘Juba,’ which always remains in Zanzibar waters (511), collected by 
Crossland. 
Fossil. Throughout the Tertiaries of Hurope from the Bartonian of Italy, 
occurring in England, France, Austria, Russia, abundantly in Italy, Algiers, 
and Tunis. 
SCHIZOPORELLA UNICORNIS, var. (Plate 12. fig. 11.) 
There is a form concerning which it is doubtful whether it should be 
separated as a variety or not. The zoarium is Hemescharan, and often the 
adnate portion throws up tubular or cup-shaped growths, and the polypides 
extend diagonally across the zocecium with the oral aperture in one corner. 
* Ann. Mag. Nat. Hist. ser. 6, vol. viii. p. 52, pl. vi. figs. 4, 5 (1891). 
eel ee 
hae, ti 
Pe ee ar ee ee 
