286 



NOTE ON NAUTILUS MOKATTAMENSIS, A. H. FOOED, FROM 

 THE EOCENE OF EGYPT. 



Ey G. C. Chick, F.G.S., of the British Museum (Natural History). 



Published by permission of the Trustees of the British Museum. 



Eead 9th April, 1915. 



PLATE VIII. 



The species Nautilus mohattamensis was founded by Dr. Fooid ^ upon 

 two fragments in the British Museum. Of these, one,- from tlie 

 Eocene of tlie Mokattam range near Cairo, was figured, and muy 

 therefore be regarded as tlie type. 



The species was described as follows: "Shell (cast) inflated, 

 somewhat compressed on the sides, rather narrowly rounded on the 

 periphery. Aperture very wide, semi-lunate. Umbilicus small, 

 with steep sides. Septa approximate. Sutures flexuous, forming 

 a conspicuous forwardly-directed lobe [saddle] in the umbilical 

 region, then curved backwards in a broad and shallow sinus, and 

 again a little forwards, ;iud making a narrow [? shallow] but distinct 

 sinus on the periphery. The position of the siphuncle is not seen. 

 !None of the test is present." 



Nautilus mokattamcnsis. — a, front view of the type-specimen ; b, lateral 

 view of the same. Eocene: Mol^attam i-ange, near Cairo, Ep;ypt. A little 

 less than one-half of the natural size. Original in the British Museum 

 Collection, Geol. Dept., register number 3404. (After Foord.) 



Tlie figures do not, however, give quite a correct idea of the fossil. 

 The specimen consists of the natural cast of about one-half of a whorl 

 of the septate ])ortion of a shell ; the outer portion of the anterior 

 part of the specimen is very tuucIi eroded, more so than is shown in 

 the side view given by the author (see fig. lb), so that the form 

 of the cross-section of the whorl is not quite correctly represented in 

 the front view accompanying tlie author's description (see fig. \a); 



' A. H. Foord, Cat. Foss. Ceph. Brit. Mus., p. ii, 1891, pp. 329, 394, 

 figs. 85a, b. 

 British Museum Collection, Geol. Dept., register number C. 3404. 



