'M MSCOPORELLID^. 



14. Discoporella annularis, 



" Discoid, hollowed in the ceutre, surrounded hy a raised border ; 

 outer border thin and wide. The whole surface, in the centre 

 as well as on the raised portion, furnished with tubes arranged 

 more or less distinctly in rays ; the tubes, though less closely 

 aggregated than in I), comphinata, are wider apart in the centre 

 than on the ajinular elevation ; apertures round, unarmed." 



Discosparsa annularis, Heller, I. c. p. 12.3. 



Hah. Adriatic. 



Probably =Z). mediterranea. 



15. Discoporella mellevillensis, D'Orb. 



" Much depressed, flattened beneath, convex above ; rays elevated, 

 wide apart, and few in number." 



Discoeavea mellevillensis, D'Orb. Pal. Franq. p. 9o9. 



Hah. Port Melleville (? Melville). 



M. d'Orbigny's Tuhulipora {Unicavea, 1852) ch/peiformis (Voy. 

 d. I'Amer. Mer. Polypiers, p. 19, pi. 9. figs. 4-6) appears to be 

 merely the young state of a Tuhulipora like T. fiabellaris (vide 

 Plate XXIV. fig. 1). 



2. TENNYSONIA, Busk. 



Zoarium stipitate, irregularly branched or lobate ; lobes sub- 

 triangular, forked at the end ; orifices of cells even with the surface, 

 arranged in straight uniserial lines from the median angle to the 

 border of the lobe ; interspaces porous. 



Tennysonia, Busk, Quart. Journ. Mic. Sc. vii. (1867), p. 240, pi. 36. 



1. Tennysonia stellata. (Plate XXXI. fig. 6.) 



The only species. 



Hah. Cape of Good Hope {Mrs. Gatti/'). 



This form is placed very doubtfully in the present family, and 

 should probably be regarded as a Heteropora. 



3. RADIOPORA, D'Orb. 



Zoarium adnate, crustaceous, spreading irregularly, and composed 

 of confluent disks like those of Discoporella ; surface reticulate or 

 cancellous ; cells disposed in serial Hues radiating from the centres 

 of the constituent disks. 



Radiopora, UOrh., 1847, Pal. Franq. p. 992. 



In the majority of the fossil species referred by M. d'Orbigny to 

 his genus Radiopora, the zoaria arc more or less rounded or bulbous, 



