208 MARINE BIOLOGY OF THE SUDANESE RED SEA. 
point from base to apex, and all being quite straight. The gastrally directed 
apical ray is frequently as long as the basal ray, 
(8) (Text-fig. 6, b,c). Quadriradiates, not quite so large as the previous 
and with the paired rays slightly curved, are also present. This slight 
curving tends to bring the axes of the paired rays to lie nearly in a 
straight line. Instead of tapering uniformly and ending in a sharp point, 
? a 
ae) 
Lie e 
or 
Fig. 6.—Spicules of Leucilla erosslandi, all x 60. 
A 
} LDS 
ae 
the ends are obtusely pointed, and the rays are of very nearly the same 
diameter for two-thirds their length. The apical ray is frequently the longest 
of the rays. The facial rays may be equal in length. 
Measurements of subdermal quadriradiates (in mm.). 
p Souci Diameter 
Basal ray. | Paired rays. | Apical ray. of rays. 
ee Shee 
PRES 3 oat ey 0°61 | 092 | 0:55 0-1 
a 
Cie eee 0-7 MOBO el AkOgsT 0-09 
RGM eicascs M ARNAiat 0:6 | 0°6 | 0°58 0-09 
} Pr 055 | 055 0:6 0-075 
| | 
