"28 j k t R# R B# NEWTON ON [NOV. I9I I, 



This species is essentially Egyptian, having been found in the 

 rocks at Siwa, Gebel Gene&e, Wadi Haggu, etc., and near Sinai. 

 A related form occurs in the Lower Helvetian beds of the Mar- 

 marican plateau near Alexandria, which has been recorded as 

 Pecten (Macroclilamys) cf. zizinia- of Blanckenhorn. 1 



Occurrence. — The matrix consists of a cream-coloured limestone, 

 within a thick rim of compact reddish-brown limestone ; a micro- 

 scopical section shows foraminifera and algae — such as Operculina, 

 numerous specimens of Amphistegina, and Lithothamnion. 



Localities. — Dr. Blanckenhorn mentions this species as occur- 

 ring also at Mersa Badia and Mersa Tobruk. The present specimen 

 was found on the plain east of Benghazi. 



Anadaka cf. ttjkonica (Dujardin). (PI. XLIII, figs. 12 & 13.) 



Area turonica Dujardin, ' Les Couches du Sol en Touraine' Mem. Soc. Geol. 

 France, 1837, vol. ii, pi. xviii, fig. 16 & p. 267 ; Hoernes, ' Foss. Moll. Tert.-Beck. 

 Wien ' 1864, pi. xliv, fig. 2 & p. 332. 

 Anadara turonica Sacco, ' Moll. Terr. Terz. Piemonte ' 1898, pt. 26, pi. v, fig. 14 

 & p. 24. 



Remarks. — The specimens herewith determined consist of 

 internal casts and impressions in a sandstone. Apparently the costse 

 vary numerically in the true A. turonica, as, according to Dujardin, 

 from twenty-six to twenty-eight are seen in examples from Prance, 

 whereas Vienna-Basin specimens, according to Hoernes, possess 

 thirty-five. The forms from Cyrenaica have a still greater number ; 

 and, although this is difficult to estimate exactly, it is probable that 

 they possessed between forty and fifty ribs, which are consequently 

 finer and much more microscopical in details of structure. These 

 costa3, however, possess the usual minutely nodulated summits of 

 this species, as well as the delicately transverse striatums decorating 

 the intercostal grooves. In general contour, also, the present speci- 

 mens agree quite well with this species. Prof. Sacco regards it as of 

 Helvetian age, and previously Theodor Fuchs had determined Area 

 cf. turonica from the Miocene deposits of Siwa in Egypt. 2 



Dimensions. — Length = 25 mm. ; height = 15 mm. 



Occurrence. — These casts and impressions are found in a fine 

 cream-coloured sandstone, weathering reddish brown. 



Locality. — Found on the traverse from Merj Plain to Wadi 

 Hamema. 



IV. Aquitanian. 



Included in the Aquitanian Series are certain marine Pelecypoda 

 which show a relationship to the ' Schioschichten ' fauna of Northern 

 Italy. They consist largely of pectinoid shell-remains furnished 

 with costal systems of highly ornamental designs, which were ob- 

 tained chiefly from the Ain-Sciahat area of Cyrenaica — the rocks of 



1 See D. E. Pachundaki, 'Contrib. Etude Geol. Marsa Matrouh (Mar- 

 rnarique)' Eevue Internationale d'Egypte, vol. iv, pt ii (1907) p. 12. 



2 Palseontographica, vol. xxx (1883) p. 33. 



