18 BRITISH PALZZXOZOIC FOSSILS. [Zoopuyra. 
PaLaoprora TUBULATA (Lonsd. Sp.) 
Ref. and Syn.—Porites tubulata, (Lonsd. Sil. Syst. t. 16. f. 3). Astrwopora Lonsdalei, and A. grandis, 
(D°Orb. Prod. Pal. p. 50, nom.) 
Sp. Ch.—Corallum forming large hemispherical masses of equal, regular, very thick-walled tubes, 
slightly more than half a line in diameter, and about half their diameter apart; on the surface the edges 
project and are strongly crenate, the radiating lamelle being about one third the diameter; intervening 
cellular space, very open, loose, and irregular, being most frequently a single plate from one cell to the 
other, and yery rarely more than two irregularly united, appearing in the vertical section as horizontal or 
oblique irregular vesicular plates; weathered vertical fractures shew the stellular tubes separated as long 
distinct suleated columns; diaphragms in the large tubes about two in a space equalling their diameter ; 
in the interstitial structure, the diaphragms are rather less than the diameter of the tubes apart, their 
upper surface granulated. 
From the strength of the walls of the lamelliferous tubes and the small number of the inter- 
vening cellular tubules the former often remain as slender persistant columns, often four inches in length ; 
the small diameter of the tubes, and the absence of the numerous small cellular openings of intermediate 
tubes between them, easily distinguish this abundant species from the P. megastoma (M*Coy). The two 
new names above quoted from M. D’Orbigny, are mere nominal references to the two typical figures of 
Lonsdale’s species in the “Silurian System.” The size and relative distance of the large tubes, and other 
characters are much more constant than in most of the genus. The upper surface of the diaphragms 
seems to be pitted or cellular. This species forms the type of the genus Propora of MM. Edwards and 
Haime, from the margin of the cells being prominent, and the radiating lamellee strongly developed, but I 
am unable to appreciate the grounds of generic distinction from the other species. 
Position and Locality—Abundant, forming large masses in the Wenlock limestone at Aymestry, 
Herefordshire, and Wenlock, Shropshire ; a variety (@) with a row of one or two small polygonal tubules 
between the cells, rare in the Coniston limestone of Coniston Water Head, Lancashire, and the same 
doubtful variety in the conglomerate of Alt Goch, Llanfyllin, Montgomeryshire; good specimen in the 
limestone of the same locality, and caleareous schists of Golugoed. Well-marked specimens in the schists of Alt 
Goch; Caradoc Sandstone of Mulock, Dalquorhan, Ayrshire. 
3rd Tribe. MADREPHYLLACEA. 
= (Zoantharia aporosa, Edw. and Haime. + Eupsammide, Edw. and Haime.) + Zoantharia 
tabulata, EK. and H. + Zoantharia rugosa, EB. and H. 
Corallum calcareous, simple or compound ; radiating lamelle rarely obsolete, usually well developed, each 
of two strong plates, and very numerous, always (when present) exceeding twelve in number; usually con- 
nected by transverse vesicular plates ; usually an external wall or epitheca. 
With a strong predisposition to view the Oyathophyllacea and Caryophyllacea as separate tribes equalling 
the Madreporacea in value, I carefully studied a considerable series of recent and fossil corals with the 
growing conviction that the grounds of separation hitherto stated were insufficient, viz. the absence of 
fission, the greater strength of the interstitial plates in proportion to the lamellze, and some obscure nume- 
rical properties of the lamellee, in the former group. The last point of difference (if it exists) has never 
been definitely stated, and I believe is incapable of definition, and fission of the centre is well known to 
oceur in the Cyathophyllum (Strephodes) Helianthoides of Goldfuss, as well as in all the species of Diphy- 
phyllum, which latter, in other respects, are highly typical Cyathophylla: 1 therefore prefer, for the present, 
falling back on Blainville’s larger group Madrephyllacea as the third tribe of the Zoantharia, and con- 
sidering the groups just mentioned, as well as the other main groups of many-rayed corals, to form dis- 
tinct families only therein. 
On this view the tribe would contain the following families: 1, MMilleporidw; 2, Cyathophyllide ; 
3, Astreide; 4, Oculinide ; 5, Fungide; 6, Turbinolide. 
