38 FOSSIL ASTEROIDEA. 
2. Muropaster Manretui, Porbes, sp. Pl. XIII, figs. 2a—40b. 
PENTAGONASTER SEMILUNATUS, Parkinson, 1811. Organic Remains of a 
Former World, vol. iii, p. 3, 
pl. i, fig. 1 (mon Linck). 
? GONIASTER SEMILUNATA, Mantell, 1844. The Medals of Creation, 
London, vol. i, p. 338, lign. 75 
(non Linck, ? nee Parkinson). 
GontastTER (Gontopiscus) Manretit, Forbes, 1848. Memoirs of the Geological 
Survey of Great Britain, 
vol. ii, p. 472. 
— —_ — Forbes, 1850. In Dixon’s Geology and 
Fossils of the Tertiary and 
Cretaceous Formations of 
Sussex, London, 4to, p. 332, 
pliscxins figs: Wile: 
— — Morris, 1854. Catalogue of British Fos- 
sils, 2nd ed., p. 81. 
? _ MANTELLI, Mantell, 1854. The Medals of Creation, 
London, 2nd ed., vol. i, p. 307, 
lign. 98. 
AstTRoGoNIUM MaNTELLuI, Dujardin and Hupé, 1862. Hist. Nat. 
Zooph. Eehin. (Suites A 
Buffon), p. 399. 
GonrasTER (Gontopiscus) Manrexut, Forbes, 1878. In Dixon’s Geology of Sussex 
(new edition, Jones), p. 366, 
pl. xxvi, figs. 11, 12. 
Body of medium or rather small size. General form depressed. Abactinal 
surface flat, with the area circumscribed by the supero-marginal plates plain and 
rather sunken below the level of the median convexity of the border formed by 
these plates. Actinal surface plain, or may be a little convex in consequence of a 
tendency to a slight upturning of the rays in some examples. Marginal contour 
pentagonal, with sides faintly lunate, or in small examples they may be almost 
straight. The major radius measures scarcely one-third more than the minor 
radius. Margin rather thin, but well rounded. 
The supero-marginal plates are four in number, counting from the median 
interradial line to the extremity, or eight from the tip of one ray to the tip of 
the adjacent ray, exclusive of the odd terminal or ‘‘ ocular” plate in each case. 
In one example, which is figured by Forbes in Dixcn’s ‘Geology of Sussex,’ 
