66 MARINE BIOLOGY OF THE SUDANESE RED SEA, 
red, but amongst the red spindles are some with intermediate light-pink 
shades. 
Their distinctive feature lies in the remarkably fine serration of the edges 
of the spindles. This is a constant feature no matter what their dimensions 
or colour may be. 
The lower cortex contains markedly spinose irregular bodies, often some- 
what star-shaped, very spinose spindles, spinose clubs, spinose triradiates, 
spinose bicuspids. 
The following measurements were taken of length and breadth in milli- 
inetres :— 
Spinose spindles : 1x01; 0°75 x 0-1 ; 0-4 x 0:12 ; 0°33 x O01; 0°3 x OL: 
0:25 x O°L; 0:23 x 0:075. 
Spinose triradiates : 0°5 ; 0°33 ; 0°3=length of the three arms. 
Spinose bicuspids: 0°75 x O°1. 
Spinose clubs: 0°18 x 0°13. 
The canal-walls in every specimen are witbout spicules. 
The colour of the colonies in spirit varies somewhat, the colour depending 
on that of the spicules. Where the spicules are red, the colony is reddish ; 
where there are a considerable number of white or light yellow spicules, the 
colony is proportionately lighter in tint. 
Locality —From a muddy bottom, at a depth of 12 fathoms, Mersa Abu 
Hamama, Sudan. 
Order III. PSEUDAXONIA, G. von Koch. 
MELITODES CoccINEA (/illis) (=Isis coccinea, Hillis). (Plate 6. figs. 1 & 2.) 
The collection includes numerous specimens which are referable to Hllis’s 
Tsis coccinea. From Ellis’s figure and description there can be almost no 
doubt that he referred to forms like the present specimens, which must, 
however, be referred to the genus Melitodes. 
The specimens are of a brilliant crimson or scarlet colour, and there is 
one yellow fragment. The most frequent mode of branching is that figured 
by Hllis,—a broad fan, with dichotomous branches almost all in one plane, and 
without anastomosis. In other specimens, however, the branches do not spread 
out in a broad fan, and anastomosis is frequent. The colonies stand erect, 
reaching a height of 4 cm. and a breadth of 2-4 cm. In some cases colonies 
erew so close to one another that their bases formed a continuous sheet. 
Solitary colonies show most clearly the typical fan-like form. 
The internodes, which curve slightly in different planes, vary in length 
from 5-10 mm. The nodes are very short, 1-2 mm., and are not distinctly 
marked in the intact colonies. On the thinner twigs the verrucee are mostly 
along the edges, and a somewhat flattened appearance thus results. On the 
