Ixxiv BRITISH FOSSIL CORALS. 
2. Genus MoRTIERIA. 
De Koninck, Anim. foss. du Terr. carbon. de Belgique, p. 12, 1842. 
Corallum having the form of a bi-concave disc, presenting a radiate structure and 
numerous costae. 
Typ. sp., Mortieria vertebralis, De Konincek, loe. cit., pl. B, fig. 3. 
3. Genus CYCLOCRINITES. 
Bichwald, Uber das Silurische Schichten-System in Esthland, p. 192, 1840. 
Corallum composite, astreiform. Calices hexagonal and shallow. Septa well charac- 
terised, but not extending to the centre of the visceral chamber, which appears to be 
occupied by small tabulz. (?) 
Typ. sp., Cyclocrinites Spaskii, Eichwald, Die Urwelt Russlands durch abbildungen erlaeutert, p. 48, 
tab. i, fig. 8, 1842. 
Order 11. 
ALCYONARIA. 
Alcyoniens, Audouin and Milne Edwards, Recherches sur les Anim. sans Vertébres faites aux iles Chausay, 
Ann. des Se. Nat., Ist series,, vol. xv, p. 18, 1828; Zoophytaria, Blainville, Manuel d’Actinologie, p. 496, 
1834; Zoophyta asterotdea, Johnston, Brit. Zooph., p. 164, 1838; Aleyonaria Dana, Exploring Expedition, 
Zooph., p. 586, 1846 ; Anthozoa asteroidea, Johnston, Brit. Zooph., 2d edit., p. 138, 1847. 
Polypi with bi-pinnate tentacula, and only eight perigastric membranaceous lamine, 
containing the reproductive organs. 
Alcyonaria have, in general, their dermal tissue consolidated by isolated spicula or 
nodular concretions only, and very rarely present a vaginal polypidom similar to that of 
the Zoantharia; but even when that is the case, the visceral chamber is never subdivided 
by any longitudinal septa, and consequently the calice never presents any appearance of 
radii. In general, the corallum is entirely composed of epidermic tissue, (or basal secretion, 
Dana,) and constitutes a sort of stem or axis in the centre of the compound mass formed 
by the gemmation of the Polypi. This sclerobasis is always covered by soft dermic 
tissue, and increases by the addition of concentric layers. 
This order is far from being as numerous as the preceding division of Corallaria, and 
comprises three natural families,—Alcyonide, Gorgonide, and Pennatulidee. 
