The Medals of Creation, Volumes 1 and 2 / First Lessons in Geology and the Study of Organic Remains

by Gideon Algernon Mantell

[439] König, Icones Foss. Sect. fig. 54. These two species are now referred to the genus Zanthopsis.

A species of Crab, characterised by its relatively large claws, is common in the soft Tertiary limestone of Malta; and examples, in a fine state of preservation, are often seen in cabinets; see Wond. p. 251.

I am not aware that vestiges of more than one genus of brachyurous crustaceans have been observed in the British Secondary formations; namely, the Podopilumnus Fittoni (M‘Coy), from the Greensand of Lyme Regis: but several small species belonging to the anomurous group have been found in the Galt.

In the Galt at Ringmer, a village near Lewes, I discovered, many years since, four or five species of small crustaceans, which are figured and described, Foss. South D. pl. xxiv.; their natural relations were pointed out to me by the late eminent naturalist, Dr. Leach. Specimens of two of the species have since been collected at Folkstone, but as these are only the carapaces, no additional light has been thrown upon the structure of the originals.

The smallest species consists of the carapace or cephalo-thoracic segments, united into a transversely obovate, obscurely trilobate shell, the surface of which is covered with minute irregular papillæ; with four tubercles on each lateral portion, and an irregularly tuberculated dorsal ridge (see [Lign. 168], fig. 1, 1a.); it probably belongs to the genus Etyus; and I have named it Etyus Martini, in honour of my friend, P. J. Martin, Esq., author of several excellent Memoirs on the Geology of Western Sussex.

Lign. 168. Fossil Crustaceans: nat. Galt. Near Lewes.]

Fig.	1.—	Etyus Martini (G. A. M.): showing the empty carapace or shell. Ringmer.
	1a.—	The dorsal surface of the same.
	2.—	Corystes[440] Stokesii (G. A. M.). Ringmer.
	3.—	Corystes[440] Broderipii (G. A. M.). Ringmer.
	3a.—	The under surface of the same species, displaying the sternal plates and the bases of the claws, three of which are marked a, a, a.

[440] These two crustaceans are included in the fossil genus Notopocorystes, established by Professor M’Coy, 1849.