242 
RADIOPOKfD.?:. 
Atfinities. 
This species is most nearly related to S. landrioti (Mich.), from 
which it differs hy haying a pitted instead of a tubercular zoarium, 
and circular instead of polygonal zooecial groups, which are not 
sharply separated. The zoarium in the type-specimen is also 
thinner. 
D. 3027. The type-specimen iucrusting a Terebratula, with Cerxopora coUin 
(d’Orb.). Lower Greensand. Farringdon. Figd. PI. V. Figs on, c. 
Old CoU. 
UXREPRESEXTED SPECIES. 
1. landrioti (Michelin), 1841. 
Srx. Ceriopora landrioti, Michehn, 1841. Icon. Zooph. p. 2, pi. i. fig. 10. 
Radiopora ,, d’Orbigny, 1850. Prod. Pal. vol. ii. p. 140. 
,, ,, d’Orbigny, 1851. Bry. Cret.pl. 648, tigs. 5-7. 
Semimulticavea landrioti, d’Orbigny, 1853. Ibid. p. 980. 
Lichenopora ,, Pergens, 1890. Rev. p. 382. 
Char. — Zoarium a large, irregular, incrusting sheet. The surface is tubercular. 
Sub-colonies polygonal, with a central depression, and long, straight, crowded, 
radial lines of apertures, with usually from four to six apertures in each line. 
Distrik. — Albian; Grandpre and St. Loup, Ardennes. 
Aptian: Sainte-Croix, Yaud. 
2. macropora, Hamm, 1881. 
Syx. Semimulticavea macropora, Hamm, 1881. Bry. mastr. Ob. -Sen. i., Cycl. 
p. 41. 
Char. — “Zoarium uni- or multilamellar, proportionately massive. Zoo?cia and 
zooecial groups large. The middle area much depressed. Apertures on the 
middle area and between the radial series are much contracted by a concave 
transverse wall. Radial series short, on low ridges consisting of five or six 
together, with shghtly compressed apertures.” (Hamm.) 
Distrib. — Senouian— Maastrichtian : Maastricht. 
3. meudonensis, d’Orbigny, 1853. 
Sy>*. Semimulticavea meudonensis, d’Orbignv, 1853. Bry. Cret. p. 982, pi. 779, 
figs. 5-8. 
Lichenopora ,, Pergens, 1890. Rev. p. 383. 
,, ,, Canu, 1902. Bry. toss, ii.. Coll. Dutemple: 
Bull. Soc. geol. France, ser. 4, vol. ii. p. 14. 
Char. — Zoarium an irregular sheet. Upper surface convex. Each sub-colony 
has a large central circular depression, from which radiate about eleven Hnes of 
apertures, containing about three or four apertures in each line. 
Distrib. — Senonian — Maastrichtian : Meudon, near Paris ; Chavot. 
