132 MARINE BIOLOGY OF THE SUDANESE RED SEA. 
There are about 15-17 tentacles, and the ovicell is not closed by the 
operculum. 
Although there is a considerable amount of material, it has not been 
possible to find the stolon from which it grows, or the younger zoccia, 
and it had all evidently been torn away from the surface on which it 
grew. As I have already stated, Alysidiwm parasiticum, Busk, is rooted by 
corneous tubes, which sometimes have calcareous nodes from which the 
stalk of the sub-colony grows, but I consider that A. parasiticum must be 
placed under Mucratea. 
The North Italian fossil Unicrisia tenerrima, Reuss, belongs to the genus 
Catenaria*. 
Loc. Adriatic; Naples; Capri; Rapallo; Cette, 70-80 met. (Calv.) ; 
Corsica, 35 met.: Maderia; Manaar (7Th.); Andamans (Th.). Khor Shinab, 
10-12 fath. (3); from Mediterranean ship docked in Suez (9); Nersa 
Makdah (12) ; Floating Stage, Suez (15), Khor Dongola (19), Suakim ; 
Wasin, Brit. E. Africa, 10 fath. (501) ; Ras Osowamembe, Zanzibar Channel, 
10 fath. (504); Prison Island, Zanzibar, 8 fath. (505) ; Chuaka, Zanzibar (508), 
all collected by Crossland. 
SCRUPOCELLARIA. JOLLOISU (Savigny § Audouin). (Plate 10. figs. 5-10.) 
Acarmarchis Jolloisii, Aud. “Description de Egypte,” Hist. nat. p. 240; Savigny, 
pl. 11. fig. 2 (on plate “ Cellaires ”). 
Zoarium large (over 30 mm.), spreading out in fan-shape ; many zocecia 
in an internode (17 counted in one case). Zocecia with large, wide, nearly 
round area, having a small spine at each upper corner, and one stout one, 
representing a scutum, across the middle of the area ; along the median line 
of the zoarium a small triangular avicularium to each zocecium, pointing 
downwards. The ovicells are wide, with large perforations over the surface 
and a thickened band at the proximal edge. 
On the dorsal surface the divisions between the zocecia are very wide, 
as figured by Savigny, and there is a large vibracular chamber near the 
proximal end of the zocecium, with a radicle chamber below the vibracular 
chamber. The vibracular setze are about the length of two or three zocecia, 
and are smooth, recurved at the end. There is one vibraculum at a 
bifurcation. The radicles are large smooth tubes, often connected to the 
other branches as in Canda arachnoides, Lamx. 
There are vermiform bodies at the side of the zocecium (fig. 10), extending 
to the proximal end, but starting from the fleshy mass at the distal end. 
In one case there are oval masses in the vermiform body which show 
ridges, but this may be a postmortem change. The whole organ must be 
compared with the bodies I described t+ in Bugula bicornis, Busk, though 
* Waters, Quart. Journ. Geol. Soc. vol. xlviii. (1891) p. 5, pl. 1. fig. 11. 
T Résultats du Voy. du 8.Y. ‘ Belgica, Bryozoa, p. 21, pl. 1. fig. 4 (1904). 
