332 CRETACEOUS ECHINODERMATA. 
intermediate marginal plates four, equal, broadly oblong, coarsely mammillato- 
punctate, conspicuously marginated. Inferiors similar. Superior oculars large, 
depressed, rather obtuse, similar to the intermediate laterals, but broader out- 
wardly and slightly tumid. Ossicula of disc hexagonal. 
Upper chalk. A very fine species, not uncommon. The specimen figured 
formed part of John Hunter’s collection, and may be seen in the College of 
Surgeons. 
Goniaster (Goniodiscus) Parkinsoni. . (Tab. XXI. fig. 10, 11; 
Tab. XXII. fig. 4,5, 7.) C. 
(Asterias regularis, Parkinson, O. R. iii. t. 1. f. 3.) 
Body pentagonal, with gently lunated sides. Superior intermediate marginal 
plates six, oblong, plain, gently curved, granulato-punctate or nearly smooth, 
and margined according to their state of preservation. Inferiors wider. Supe- 
rior oculars triangular, obtuse, as long and much broader externally than the 
laterals, gibbously convex, sculptured like the rest. Ossicles of disc hexage- 
nal, granulated. Ambulacral ossicula transversely oblong, 3—-4-grooved. Oral 
plates broadly triangular. 
The commonest of all the white chalk star-fishes. Parkinson wrongly identified 
it with the figure and name of a living species. 
Upper and lower chalk. Kent, Sussex, &c. 
Goniaster (Goniodiscus) Mantelli. (Tab. XXIII. fig. 11 & 12.) C. 
(Asterias semilunatus, Parkinson.) 
(Goniaster semilunata, Mantell, Medals, vol. i. p. 338, cut 75.) 
Body pentagonal, with lunate sides and projecting angles. Superior inter- 
mediate marginal plates six, oblong, narrow, tumid, abrupt, punctate, marginate : 
markings distant and coarse, sometimes presenting the appearance of moniliform 
granules. Inferiors nearly plain. Superior oculars much larger than the mar- 
ginals, very prominent, punctate. Ossicula of disc punctate. 
Some specimens of this not rare upper chalk species aphroach very near the 
last, but usually they are easily distinguished. 
Parkinson wrongly identified it with the figure and name of a recent species. 
