90 PROCEEDIJVGS OF THE GEOLOGICAL SOCIETY. [DeC. 21, 



2. Notes on some neiv Crustaceans /rom the Lower Eocene of Ports- 

 mouth. By Henry Woodward, Esq., E.G.S., E.Z.S., of the 

 British Museum. 



[Plate IV.] 

 Having been favoured by Messrs. C. J. A. Meyer and Caleb Evans 

 with the opportunity of examining three new Crustaceans recently 

 obtained by them from the Lower Tertiary Deposits exposed during 

 the excavations for the "Dockyard Extension Works" in Ports- 

 mouth Harbour, I beg to submit the following notes thereon. 



I. Family Corystid^. (Genus Palceocorystes, Bell.) 



This family, represented at the present day by the genus Corystes 

 common on our own coast, and in the Chalk, Greensand, and Gault 

 by the genera Palceocorystes and Eucorystes, has now been discovered 

 in the Lower Eocene, at Portsmouth, by Mr. Caleb Evans, E.G.S. 



The specimen (see Plate IV., figs. 1 a, h), although far from per- 

 fect, is sufficient to indicate at once the genus to which it belongs, 

 namely Palceocorystes, and also that it is specifically distinct from 

 those occurring in the Cretaceous rocks, already described by Prof. 

 Bell and others *. The carapace measures one inch in length ; but 

 (both its anterior and posterior borders having been injured) it 

 was, originally, probably nearly one-fourth of an inch longer. In 

 breadth it measures 10 lines. Some portion of the anterior (orbital 

 and suborbital) border can still be traced out ; but the rostrum is 

 quite destroyed. The surface of the carapace is smooth and devoid 

 of ornamentation, save a few widely scattered and very minute 

 puncta ; but where the delicate cortical layer has been removed, the 

 carapace presents a finely granular structure. The two sigmoid 

 markings, observable on the carapaces of aU the Corystidse are also 

 clearly to be seen in this examjDle. 



On the underside the branchiostegal pieces (6r) are traceable, 

 also the basal joint (m) of one of the maxilHpedes (see Plate IV. 

 fig. 16).. 



I propose to name this form Palceocorystes glabra. Previously to 

 the discovery of this crab no species of Palceocorystes had been met 

 with in any bed younger than the Maestricht Chalk, where a species 

 named P. {Notopocorystes) Miilleri has been noticed by Count von 

 Binkhorst, which much resembles P. glabra, save that the sigmoidal 

 markings seen on the latter are absent in the former species. (See 

 Plate IV. fig. 2.) 



This is the second family of Crustaceans living at the present day, 

 and met with fossil in the Maestricht Chalk, which I have had the 

 pleasure of recording as occurring also in the Eocene of the south 

 of England t. 



* See Prof. Bell's Monograph on the Fossil Crustacea of the Gault and Green- 

 sand, Palaiontographical Society, 1862, vol. xiv. p. 11, pis. ii. & iii. 



t See British Association Eeports, Norwich, 1868, on the Occurrence of Cal- 

 lianassa Batei in the Upper Marine Series, Hempstead, Isle of Wight, p. 75, 

 pi. 2. fig. 4. 



