268 MOLLUSCA FROM THE CRAG. 
The recent species Veera hyalina, Hinds, appears to be more nearly connected with 
Thetis, having an external ligament on a thin and semi-transparent shell, differing 
thereby from our fossil, which is a thick one. The two shells figured by Messrs. 
Reeves and Adams in the ‘Zoology of the Voyage of the Samarang,’ may perhaps 
belong to Zhetis, but the position of the ligament is not stated, and the shells are 
described as being quite smooth and thin. 
The Cretaceous fossils of India and Westphalia, assigned to this genus, have not 
as yet had their characters sufficiently well determined. 
1. PoroMys GRANULATA, Wyst and Westendorp. Tab. XXX, fig.’5, a—/. 
CoRBULA GRANULATA. Nyst and West. Nouv. Rech. Coq. Foss. d’Anv., p. 6, No. 10, 
pl. 3, fig. 3, 1839. 
—_ ? — Nyst. Coq. Foss. de Belg., p. 71, pl. 2, fig. 6, 1844. 
— es Jeffreys. An. and Mag. Nat. Hist., vol. xix, p. 314; and vol. xx, 
Pomspey lO: 
PoroMYA ANATINOIDES. Forbes. Agean. Invert. Brit. Assoc. Report, p. 191, 1843. 
—  GranuLtata. Forb. and Hani. Hist. of Brit. Moll., p. 204, pl. 9, figs. 4—6, 
1848; and Animal, pl. w, fig. 2, 1853. 
Empia Koren. Lovén. Ind. Moll. Scand., p. 46, 1846. 
Spec. Char. Testa ovatd, ventricosd, subequilaterali ; antice rotundatd, posticé trun- 
catd, et obtuse angulatd; aculeis minutissimiss criberrimis aspera; umbonibus prominenti- 
bus ; dente unico obtuso. 
Shell ovate, ventricose, slightly inequilateral; anterior side rounded, posterior 
truncated, with an obtuse keel or ridge retreally from the umbo to the ventral 
margin; beaks prominent; one obtuse tooth. 
Length, inch. Height, 3 inch. 
Locality. Cor. Crag, Ramsholt, Sutton, and Gedgrave. 
Recent, Aigean, British, and Scandinavian Seas. 
About a dozen disconnected valves have been obtained by myself, several of them 
sufficiently perfect for fair comparison, and I have considered them as identical with 
the Belgian fossil and the Aigean and Scandinavian shell. 
The hinge of the right valve is furnished with one large obtuse tooth, situated 
immediately beneath the umbo, and in the left there is a corresponding cavity between 
two small prominences for its reception; behind these, and within the dorsal margin, 
is a depression wherein, I presume, the ligament was placed: this cavity is divided by 
a small ridge, which appears to have separated the cartilage from the ligament, and 
the latter probably was visible externally when the valves were closed: there is a 
small depression on the siphonal side at the dorsal edge, what may perhaps be 
called the corslet, produced probably by the opening of the valves; but there is no 
ridge or fulcrum for the support of an evferval ligament. The impressions by the 
