xlviii BRITISH FOSSIL CORALS. 
9. Genus HALoMITRA. 
Dana, Zooph., p. 311, 1846. 
Corallum composite, differig from the preceding genus by its very long and numerous 
septa. 
Typ. sp., Halomitra pileus, Dana, loc. cit., p. 311; Fungia pileus, Lamarck, Hist. des An. sans Vert., 
t. ii, p. 237. 
10. Genus Popopacta. 
Milne Edw. and J. Haime, loc. cit., p. 71, 1849. 
Corallum composite, cyathiform, and adherent by its basis. Ca/ices as in Halomitra. 
Typ. sp., Podobacia cyathoides, nob.; Agaricia cyathoides, Valenciennes MSS., in the Gallery of the 
Paris Museum. 
ll. Genus LitHactrinta. 
Lesson, Illustr. Zool., 1833. 
Corallum composite, free. Calices of one sort only, and not radiate. Seta short, 
and separated by very thin, transverse laminee, which appear to be analogous to columellee. 
Typ. sp., Lithactinia novehybernia, Lesson, loc. cit., vi, figs. 1, 2. 
12. Genus PoLYPHYLLIA. 
Quoy and Gaimard, Voy. de l’Astrolabe, Zooph., p. 184, 1833. 
Corallum composite, free, and having calices of two sorts ; the central ones sub-radiate, 
and arranged in a line. 
Typ. sp., Polyphyllia pelvis, Quoy and Gaimard, loc. cit., pl. xx, figs. 8—10. 
13. Genus Zoortts. 
Dana, Zooph., p. 318, 1846. 
Corallum composite. Septa of two sorts; the large ones radiately prolonged quite to 
the margin; the mtermediate much smaller, and those only interrupted by the calicular 
fossulze or orirmns. 
Typ. sp., Zoopilus echinatus, Dana, op. cit., p. 319. 
Third 'Tribe— LOPHOSERIN A. 
Plate (or basal wall) not perforate nor echinulate. No epitheca. 
