R. W. H. ROW—REPORT ON THE SPONGES : NON-CALCAREA. 329 
region. Throughout the length of the process the wall of the tube is very 
thin and rarely exceeds 3 mm. in thickness. 
The colour in spirit is dirty white. . 
The skeleton arrangement and the spicular measurements agree with 
Keller’s description. 
Locality. All the specimens were obtained from buoys in Suez Bay. 
Mistribution. Red Sea. 
SIPHONOCHALINA COMMUNIS, Carter. 
Synonymy :— 
1880, Stphonochalina communis, Carter (7 a). 
1905. Siphonochalina communis, Dendy (11). 
This species is represented in the collection by three specimens representing 
two varieties. 
Var. a—The first variety is represented by two fairly large specimens, the 
largest possessing five tubular processes 20-25 mm. in diameter. They agree 
very closely with Dendy’s figure in the report on the Ceylon Sponges (11). 
The tubular processes are quite smooth on the surface, but they exhibit a very 
slightly raised and rather inconspicuous reticulation on the surface, as do 
Dendy’s specimens. At the summit of each of the tubes is an osculum whose 
diameter is on the average 4 mm. 
The colour of the specimens is yellowish white. 
The skeleton consists of an irregular reticulation of spicule-covered spongin- 
fibres, in which main fibres can be distinguished from secondary fibres, for 
the main fibres, which run somewhat irregularly, are covered by several rows 
of spicules, while the secondary fibres have the spines arranged uniserially. 
The spicules are oxea, straight, smooth, and cylindrical. They are of the 
same diameter for the greater part of their length, and abruptly but sharply 
pointed at each end. They measure 0°1 mm. in length and 0:002 in 
diameter. 
Var. 8.—The second variety is represented by a single specimen, consisting 
of two tubes only. These tubes are somewhat low, not being more than 
12 mm. in height, but are of distinctly larger size than those of var. a, the 
largest measuring 33 mm. in diameter. The second tube is a small one, 
arising as an offshoot from the first, and measures 15 mm. in diameter. They 
each possess a widely open osculum at the summit, the diameter of the oscula 
being 8 mm. in the case of the larger tube and 4 mm. in the case of the 
smaller tube. 
The surface of this specimen is even smoother than that of the two previous, 
there being no reticulation visible in this case. 
The colour in spirit is dark brown. 
The skeleton is very similar to that of var. #, but the main fibres run more 
regularly and do not contain quite so many spicules. 
