LICHEN OPOKA. 
257 
D. 3508. 
D. 3513. 
B. 3514. 
B. 3539. 
B. 3599. 
B. 5144. 
B. 5145. 
B. 10,878. 
Three worn flat-based zoaria, with fusiform bundles and deep central 
cavity (on slide). Maastrichter Kalk. Maastricht. Van Breda Coll. 
A tube Avith twenty zoaria, flat-based and bigb-ridged. Maastrichter 
Kalk. Maastricht. Van Breda Coll. 
Two young but regularly radial zoaria ; the younger shows the 
beginning of ridges from the cariosa stage. Maastrichter Kalk. 
Maastricht. Van Breda Coll. 
Tavo compound zoaria (on slide), consisting of four layers of sub- 
colonies Avith triangular ridges. Maastrichter Kalk. Maastricht. 
Van Breda Coll. 
A well-preserved zoarium, with high, short ridges and a large, deep, flat 
central depression. Maastrichter Kalk. Maastricht. Van Breda Coll. 
Two zoaria of var. fusiformis, like the figured specimen B. 3510. 
Maastrichter Kalk. Maastricht. Van Breda Coll. 
A young zoarium of the var. sellula ; the base is flat and narrower 
than the upper surface of the disc which overhangs the vertical 
edge ; the structure of the groups when seen from above agrees 
Avith that of Fig. 62 (B. 3510), hut they extend for a shorter distance 
towards the middle of the disc. Maastrichter Kalk. Maastricht. 
Van Breda Coll. 
A zoarium, labelled Lichenopora elatio7',xaxe.^' Maastrichter Kalk. 
Maastricht. Gamble Coll. 
UNREPRESENTED SPECIES. 
1. boletiformis (d’Orbigny), 1854. 
Syn. Tecticavea boletiformis, d’Orbigny, 1854. Bry. Cret. p. 991, pi. 781, 
figs. 8-12. 
Radiocavca ,, Hamm, 1881. Bry. mastr. Ob. -Sen. i., Cycl. p. 43. 
non Lichenopora Waters, 1884. Foss. Cycl. Austr. : Quart. 
Journ. Geol. Soc. vol. xl. p. 695, pi. xxxi. 
figs. 20, 21. 
Lichenopora {Radiocavca) diadema, pars, Pergens, 1889. Bev. p. 382. 
Char. — Zoarium growing in superposed groups, which remain isolated ; radial 
groups of apertures alternately long and short, well raised above the interradial 
valleys. 
Dibtrib. — Senonian : Ciply, Belgium. 
Maastrichtian : Maastricht. 
Aff. — T he specimens from Aldinga referred to this species by Waters are 
described by him as forming confluent continuous sheets. 
2. cribrosa, von Renss, 1846. . 
Syn. Lichenopora cribrosa, von Eeuss, 1846. Verst, bohm. Kr. p. 64, pi. xiv. 
fig. 10. 
Char. — Wholly indeterminable. 
Distrib. — Cenomanian: Bilin and Weisskirchlitz, Bohemia. 
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