INTRODUCTION. XXXV 
44. Genus TRIDACOPHYLLIA. 
Blainville, Dict. des Sc. Nat., vol. lx, p. 327, 1830. 
Corallum short, and composed of corallites, arranged in series intimately united by their 
lateral walls, which, instead of forming a simple ridge as in the preceding genera, constitute 
very tall, foliaceous expansions, variously twisted, and terminated by asub-crenulate margin ; 
the calicular trenches broad, very deep, and winding. Colwmel/a quite rudimentary, but the 
calicular centres very distinct. Sepfa projecting very little, thin, nearly equal, and serrate. 
Dissepiments abundant, very oblique, convex, and forming long vesicules. Plate or exterior 
surface of the common wall of the corallum covered with lamellar costae, which extend from 
the basis of the mass, project slightly, and are irregularly denticulate. 
Typ. sp., Tridacophyllia lactuca, Blainyille, loc. cit. ; Concha fungiformis, Seba, Thes., v. ii, tab. cxxxix, 
No. 10; Pavonia lactuca, Lamarck, An. sans Vert., vol. ii, p. 239; Manicina lactuca, Ehrenberg, op. cit., p. 103. 
45. Genus TRACHYPHYLLIA. 
Milne Edw. and J. Haime, Comptes rend., t. xxvii, p. 492, 1848. 
Corallum short, increasing by fissiparity, and composed of very flexuous series of coral- 
lites, free laterally. Common walls strongly echinulate. Hpitheca rudimentary. Columella 
well developed, but of a very loose, spongy texture. Septa numerous, crowded, exsert, and 
strongly granulated laterally. 
Typ. sp., Trachyphyllia amarantum, Milne Edw. and J. Haime, Ann. des Sc. Nat., 3°° sér., vol. xi, 
p- 275; Amarantum saxum, &e. Rumph. Amb. Hort. vi, tab. Ixxxvii, fig. 1. 
46. Genus ASPIDISCUS. 
Konig, Icon. Foss. Sect., p. 1, 1825; Cyclophyllia, Milne Edw. and J. Haime, Comptes rend. de l’Acad. 
des Sc., vol. xxvii, p. 492, 1848. 
Corallum discoidal, with its inferior surface flat, and its upper surface convex. Coradlites 
arranged in radiating series, separated by thick and simple, crest-like mural ridges, excepting 
towards the margin of the calicular surface, where the young individuals spread out so as to 
form a broad, continuous, lamello-striate border. Co/wmedla rudimentary, but the calicules 
well individualized. Septa very thin and crowded, but not numerous in each corallite. 
common plate covered with a thick epitheca, presenting concentric stric or folds. 
Typ. sp., Aspidiscus cristatus, Milne Edw. and J. Haime, Ann. des Se. Nat., 3™ série, vol. xi, p. 277 ; 
Aspidiscus Shawi, Konig, Icon. Foss. Sect., pl. i, fig. 6; Cyclolites cristata, Lamarck, Anim. sans Vert., 
t. 1, p. 234. 
AT. Genus SCAPOPHYLLIA. 
Milne Edw. and J. Haime, Comptes rend. de l’Acad. des Se., t. xxvii, p. 192, 1848. 
Corallum columnar, erect, very dense, and formed of corallites arranged in series, 
completely united laterally.  Colwmel/a tubercular, somewhat compact.  Septa very thick, 
neither closely set nor numerous ; with their sides very echinulate, and the apex denticulate. 
Dissepiments simple and distant. 
Typ. sp., Scapophyllia cylindrica, Milne Edw. and J. Haime, Ann, des Se. Nat., 3™° série, vol. x, 
tab. viii, fig. 8. 
