176 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [NoV. 21, 



Genus and Species. 



References. 



Formations. 



Localities. 



Belemnitella 

 a fragment 





Subcretaceous 



Alenquer. 



Vendas Novas. 



Montemor ; Ven- 

 das Novas ; 

 ]\Iealhada. 



Montemor. 



Montemor. 



Lisbon. 



Lisbon. 



Praia de Macams. 



Lisbon. 



Lisbon. 



Pero Pinheiro, 

 Lisbon. 



Belemnites 



d'Orbigny, Pal. Fran?. T. 



Jurass. t. 11. f. 6. 

 Sclilotheim ; Bruguieria- 



nus, d'Orbigny, Pal. Fran9. 



T. Jurass. t. 7. f. 1-5. 



Sowerby,Min. Con.t.l23. 



n. s., t. 26. f. 6 



RUDIST 



Lamarck; d'Orbigny, Pal. 



Fran9. T. Cret. t. 549. 

 Des Moulins, Essai sur les 



Spheralites, t. 4. f. 1-3. 

 d'Orbigny, sp. Pal. Franc. 



T. Cret. t. 543. f. 4 & 5. 

 d'Orbigny, Pal. Franc. T. 



Cret. t. 552. 

 d'Orbigny, Pal. Fran?. T. 



Cret. t. 553. 





paxillosus. 



Jurassic 



Nautilus 



truncatus 



Jurassic 



TURRILITES 



Beirensis 



Sph^rulttes 

 angeiodes 



cylindracea 



Marticensis? ... 



Ponsiana 



Jurassic 



A. 



Hippurite limestone . 

 Hippurite limestone . 

 Subcretaceous . . . 



Hippurite limestone . 

 Hippurite limestone . 

 Hippurite limestone . 



Sauvagesii 



ventricosa 





Arca Olisiponensis, n. s. Pl. XIV. fig. 1 «, 1 5, & 1 c. 



Shell gibbose, subtrapezoidal, divided into two unequal parts by a 

 broad rounded keel extending from tbe umbo to the produced pos- 

 terior angle, the anterior part gibbose and rounded, the posterior flat 

 and sloping down to the straight and slightly obhque posterior mar- 

 gin. Ventral margin slightly rounded. Beaks near each other ; 

 hinge-area small. 



Surface decussated with nearly equal, fine, radiating and concen- 

 tric lines, with impressed elongated points at each intersection. 



Length 2\ inches ; breadth 3 inches ; thickness 2 inches. 



Abundant in the upper beds of the hippurite limestone on the 

 west side of Lisbon. 



This species is nearly related to A. Guerangeri, D'Orb., but has a 

 less rounded margin, a flatter posterior slope and closer concentric 

 lines, producing a more regular decussation over the surface. Most 

 of the specimens found are internal casts, but one of them shows a 

 portion of the outer shell, which appears to have been thin. 



Plate XIV. fig. 1 «. A cast of the interior. 



Fig. 1 h. The same specimen seen on the side of the hinge. 



Fig. 1 c. Portion of the surface of another specimen. 



