The Cretaceons Fauna of Pondoland. 299 



Family OSTEEID^. 

 Plate XXXV., fig. 15-17. 

 A few examples of small forms of Ostrca and Exogyra''- are 

 present in the Survey collection, but they are insufficient for specific 

 determination. 



Family PERNID^. 



Genus INOCEEAMUS, Sowerby. 

 Inocebamus expansus, Baily. 

 1855. Inoceramus expansus, Baily, Q.J.G.S., xi., p. 462, pi. xiii., 



fig. 5. 

 1871. Inoceramus expansus, Stohczka, Cret. Fauna S. India, 

 p. 401 (No. 180). 

 Non 1863. Inoceramus expansus, Schafhiiutl, Sud-Bayerns Lethaea 

 Geognostica, p. 153, pi. xxxiv., figs. 1, 2, 6. 

 Description. — Shell very lai'ge, very inequilateral, longer than 

 high ; moderately convex near the umbones, flattened elsewhere, 

 with a steep slope near the anterior margin. Umbones moderately 

 prominent, curving anteriorly. 



Surface with numerous narrow concentric ribs, separated by 

 shallow rounded interspaces. The ribs curve rather rapidly in 

 passing on to the postero-dorsal part of the shell, and cut the 

 posterior part of the dorsal margin obliquely. 



Bemarks. — This species attains a very large size. An imperfect 

 specimen belonging to the Survey was at least 180 mm. in height. 

 Captain Garden estimated that some of the specimens which he saw 

 in situ must have been nearly 3 feet in height. 



The type of I. expansus consists of the dorsal portion of a left 

 valve detached from the matrix. It is preserved in the Museum of 

 the Geological Society of London. 



I. expansus appears to be allied to I. Cripsi, Mantell.f but more 

 numerous and more perfect specimens are needed before a satis- 

 factory comparison can be made. Forms either identical with or 

 allied to I. Cripsi have been described from many European 



* For a discussion of the systematic value of the "genera" Ostrea, Exogyra, 

 Gryphea, Alectryonia, &c., see Peron, Explor. Scient. Tunisie, Descript. Brach.etc. 

 Terr. Cret. de la Tunisie (1893), pp. 107-9. 



t Foss. S. Downs (1822), p. 133, pi. xxvii., fig. 11. 



