626 MR. E. B. NEWTON ON [Nov. I9H, 



Gastropoda. 



Strombus cf. coronatus Defrance. (PI. XLIII, fig. 14.) 



Strombus coronatus Defrance, Diet. Sci. Nat. [Paris] 1827, vol. li, p. 124 

 Hcernes, ' Foss. Moll. Tert.-Beck. Wien ' 1852, pts. 2-4, pi. xvii, fig. 1 & p. 187 ; 

 Sacco, ' Moll. Terr. Terz. Piemonte ' 1893, pt. 14, pi. i, fig. 19 & p. 7. 



Remarks. — Two limestone casts represent a form of Strombus 

 allied to the coronatus of Defrance, the true species being known 

 under different names (see Hcernes and Sacco for the synonymy) 

 having been described from France, Poland, Italy, Austria (Vienna 

 Pasin, etc.), the Morean region of Greece, etc., besides a related 

 form determined by Fuchs from the Pyramids district of Egypt. 

 Its range in time is regarded by Prof. Sacco as extending from 

 the Tortonian division of the Miocene to the Astian Group of the 

 Pliocene System. The specimens are of moderate size, exhibiting 

 a widely spiral region with three or four tabulate whorls separated 

 by a canaliculate suture; the aperture is elougate and narrow, while 

 the columella terminates with a long and prominent excavation. 

 The surface shows some very obscure concentric striatums Just 

 below the summit margin of the body-whorl, and there are indi- 

 cations besides of distant nodulations on the same margin, from 

 which extend obliquely some obscure growth-lines. This form 

 is considered to be in closer relationship to Strombus coronatus 

 than to Str. bondli of Brongniart, on account of the great width 

 of the summit-region, the latter species being relatively longer 

 and more slender in its general contour. 



Dimensions. — Length = 85 mm. ; width (frontal) = 62 mm. 



Occurrence. — The specimens are associated with a cream- 

 coloured compact limestone, which has weathered reddish-brown, 

 and is apparently full of f oraminifera (Amphistegina ?, etc.). 



Locality. — Gubah . 



Pelecypoda. 



Alectryonia cf. plicattjla (Gmelin). (PI. XLIII, fig. 11.) 



Ostrea plicatula Gmelin in Linnaeus, ' Systema Naturae,' 1790, ed. 13, vol. i, 



pt. 6, p. 3336. 

 Alectryonia plicatula Sacco, ' Moll. Terr. Terz. Piemonte,' 1897, pt. 23, p. 19. 



Eemarks. — I am inclined to place here a single lower valve 

 attached to matrix, of an ostreiform shell showing external cha- 

 racters only. It is of rounded contour dorsally, posteriorly, and 

 ventrally, but truncated and obliquely margined in the anterior 

 area ; the surface is generally depressed, its chief convexity being 

 in the posterior region ; the ornamentation consists of a series of 

 five or six radial plications eqnidistantly separated, which bifurcate 

 about midway and terminate in rounded tubular extremities. 



Dimensions (lower valve). — Length = 50 mm.; height = 47 mm.; 

 diameter = 15 mm. 



The specimen compares favourably with 0. plicatula of Gmelin, 

 a recent Mediterranean species which has both its valves plicated, 



