632 ME. E. B. NEWTON ON [Nov. IQI I, 



Dimensions (lower valve). — Length = 15 millimetres; height = 

 15 mm. 



Occurrence. — In a greyish marly-looking rock containing 

 obscure Operculina. 



Locality. — Ain Sciahat. 



iEouiPECTEN of. pasinii (Meneghini). (PI. XLIV, figs. 4 & 5.) 



Pecten pasinii Meneghini, 'Pal. Sardaigne ' 1857, pi. H, fig. 13 & p. 591; 

 Schaft'er, Jahrb. K.K. Geol. Reichsanst. 1900, vol. xlix, pi. xvii, figs. 1-3 b & 

 p. 661 ; Oppenheim, Zeitschr. Deutsch. Geol. Gesellsoh. 1903, vol. lv, pi. ix, 

 figs. 2-3 & p. 162. 



Remarks. — In the various figures of Pecten pasinii the dimen- 

 sions of the valves show a greater length than height, thus differing 

 from Cyrenaican examples, which are of equal measurement in those 

 directions, namely 43 millimetres for the largest valve. The sculp- 

 ture, which is similar on both valves, is, however, somewhat the 

 same as in Meneghini's shell : that is, the costae and grooves are 

 furnished with closely-set, extremely fine, regular, and concen- 

 trically imbricating striations, this last character appearing to 

 be less accentuated than in the true P. pasinii, where the striations 

 are of rather simpler structure. Meneghini's P. pasinii was ori- 

 ginally described from Sardinia, and more recently it has been 

 recognized from Monte Brione in the Tyrol by Dr. Schaffer, and 

 from Italian localities by Dr. Oppenheim, the latter author regarding 

 the species as of Aquitanian age (' Schioschichten '). 



One of the small specimens is attached to an example of sEquipecten 

 camaretensis and another to JEquipecten zitteli. 



Occurrence. — In a grey marly matrix containing Operculina ; 

 and a doubtful fragment in a greensand matrix, weathering red, 

 from Birlibab. 



Localities. — Fountain of Apollo, Cyrene (British Museum 

 specimen — L 16342) ; and Ain Sciahat, above camp ; ? Birlibah. 



iEojnPECTEN zitteli (Fuchs). (PI. XLY, figs. 7 & 8.) 



Pecten zitteli Fuclis, Palseontographica, 1883, vol. xxx, pi. vii (ii) figs. 1-12 & 



p. 41 (23). 

 Pecten (Chlamys) zitteli Kilian, 'Mission d'Andalousie ' Mem. Acad. Sci. 



Prance, 1889, ser. 2, vol. xxx, pi. xxxiii, fig. 9 & p. 709. 

 JEquipecten zitteli Sacco, ' Moll. Terr. Terz. Piemonte ' 1897, pt. 24, p. 31. 

 Pecten (JEquipectm) zitteli R. B. Newton, Geol. Mag. 1899, p. 209 ; Blancken- 



horn, Centralblatt Mineral. &c. [Stuttgart] 1900, p. 211, and Zeitschr. 



Deutsch. Geol. Gesellsch. 1901, vol. liii, p. 108. 

 Pecten zitteli Dollfus, in Pachundaki, ' Contrib. Etude Geol. Marsa Matrouh 



(Marmarique) ' Revue Internat. Egypte, vol. iv, pt. ii, 1907, p. 32. 



Remarks. — Quite a number of pectinoid shells appear to be 

 referable to this species, which belongs to the Helvetian beds of 

 Egypt (Siwa Oasis, etc.) and the Marmarican Plateau near Alexan- 

 dria. From its variability in sculpture the species is often difficult 

 to determine, the Cyrenaican specimens offering no exception to 

 this changeable character of the ornament. Some of the valves 

 exhibit slightly tripartite or divided costse, whereas others are 

 more rounded ; lines of minute granulations frequently cover 

 the grooves and the sides of the costse, while an extremely fine 



