Prof. J. W. Gregory — Fonsil Corals from Egypt, etc. 55 



edges of the calicos are less raised. It is allied to S. turonensis 

 (Mich.)/ from the Miocene of Turin, but that has rounded corallites. 

 It differs markedly from S. tenera (Eeuss),- its nearest ally in the 

 Austrian Miocene, owing to the much greater distance between 

 the corallites in that species ; they are also more circular. I feel 

 doubtful whether this species is not merely an elliptical variety 

 of the recent Eed Sea species, S. chalcidicum (Forsk.), of which 

 a specimen from the raised reefs of Qosseir is shown on PI. VII, 

 Fig. 12. S. anomala, Felix,^ from east of Cairo has round and 

 crowded calices. 



STYLINA, Lamarck, 1816. 



StYLINA TETRA3IERA, n.SP. (PI. VI, Fig. 7.) 



Corallum massive ; upper surface subplane. 



Corallites long and narrow ; generally round and oval ; crowded. 

 The walls on the surface occur sometimes as sharp ridges, while in 

 other parts they are separated by narrow depressions. Sections in 

 the interior of the corallum show that the corallites are nearly 

 always separated by interspaces crossed by some of the costge. 



Calices very deep. 



Septa irregular; those of the first cycle very distinct; one series 

 of septa is much more conspicuous than the other ; and as this 

 series often consists only of 4 or 5 septa, some corallites have 

 a tetrameral aspect. This structure is less often noticed in sections 

 through the interior of the corallum. There are two complete cycles, 

 and the third cycle is usually incomplete. 



Columella irregular. Seen from above it is conspicuous and 

 joined to the 4, 5, or 6 largest septa, and it often projects into the 

 calice as if it were styliform. Sections show that its structure is 

 less regular; but a central styliform columella is often recognizable. 



Dimensions. — Corallum : — 



Length 160mm. 



Width 78 ,, 



Thickness 80 ,, 



Corallites : 



Average diameter 3 by 2 ,, 



Calicinal centre : 



Average distance 3 ,, 



Distribution. — Miocene : Plateau, Abu Sha'ar, H 1818. 



Figures. — PL VI, Fig. 7, part of the surface of the corallum, 

 by 2 diam. 



Affinities. — This species is one of those that serve to link Stylina 

 to the Orbicelloids, as it is in all respects a Stylina except that the 

 columella shows a tendency to become trabecular. 



1 Michelin : Icon. Zooph., p. 312, pi. Ixxv, figs. 1-2. 



^ Explanaria tenera, Reuss: Polyp. Wien. Tert., 1847, p. 18, pi. iii, fig. 2. 

 Solenastrcea tenera, Eeuss, Kor. ost. ung. Mice. : Denk. Akad. Wiss. Wien, vol. xxxi 

 (1872), p. 242, pi. vii, fig. 5. 



2 FeKx, op. cit. : Zeit. deut. geol. Ges., vol. Ivi (1904), p. 173, pi. x, fig. 3. 



