AND MOLLUSCA FROM ANGOLA, PORTUGUESE WEST AFRICA. 569 



Fam. Limid^e. 

 Lima cf. itieriana, Pictet and Koux. (PL I, fig. 9.) 



Lima parallela, Orbigny : Pal. Frangaise : Terr. Gretaces Lamellibranchia, 1846, vol. iii, pi. 416, 



figs. 11-14, p. 539, non J. Sowerby. 

 Lima itieriana, Pictet and Roux : Desc. Moll. Foss. Gres Verts, 1852, pi. xl, fig. 5, p. 484. 



Remarks. — The collection contains two limestone casts of right valves which 

 appear to present affinities with this species. They possess the same number of 

 costse, about 20 ; no ornamentation can now be traced, nor is there any evidence 

 of a thin rib occupying the grooves, which is a characteristic feature of the shell 

 when properly preserved. A resemblance undoubtedly exists between these 

 specimens and the Lima interlineata of C. A. White,* which has been recorded 

 from the- Schloenbachia inflata beds of Brazil (Sergipe). The species itself is 

 synonymous with Plagiostoma elongata of J. de C. Sowerby, which has been included 

 by Mr H. Woods in his Lima (Mantellum) gaultina. t 



Distribution. — The species ranges in Europe from the Albian to the Cenomanian, 

 but both Peron and Pervinquiere have recognised it in rocks of Cenomanian age 

 in Tunisia. 



Occurrence. — Found in a cream-coloured limestone with Neithea sequicostata. 



Locality.— No. 294— Plateau 800 feet E. of Lobito. 



Fam. Mytilid^e. 

 Volsella sp. (PI. I, figs. 10 and 11.) 



Remarks. — This genus is represented by one specimen possessing very tumid 

 valves, a gently excavated ventral margin, a pair of nearly terminal umbones, a pro- 

 minent lanceolate ligament cavity, and a concentrically striated ornamentation. 



Dimensions. — 



Length ...... 60 mm. 



■ Height . . . . . 23 „ 



Diameter (with closed valves) . . . 24 „ 



Judging from the lateral view of this specimen, there is much in its contour 

 and general appearance to connect it with Modiola siliqua of Matheron from 

 the " Craie chloritee " or Cenomanian beds of France, \ especially Orbigny's 

 interpretation of that species, § although a comparison shows that the Angola fossil 

 is furnished with much more inflated valves and is relatively wider at the anterior 

 end. It is probably a new species, although the surface ornamentation is too 



*" Contributions to the Paleontology of Brazil," Archiv Mus. Nacion. Brazil, 1888, vol. vii, pi. iii, 

 figs. 3, 4, p. 42. 



t Mon. Pal. Soc. : Cretaceous Lamellib. England, 1904, vol. ii, pi. v, figs. 16-20, p. 31. 



\ Gat. Method. Foss. Bouches-du-Rhone, 1842, pi. xxviii, figs. 5, 6, p. 178. 



§ Pal. Francaise : Terr. Cre'tace's Lamellibranchia, 1844, vol. iii, pi. 339, figs. 3, 4, p. 274. 



TRANS. ROY. SOC. EDIN., VOL. LI, PART III (NO. 15). 82 



