imperfectly -defined Species of Jurassic Nautili. 283 



It is very doubtful whether the English references to this 

 species are correct, because d'Orbigny's figure in the i Paleon- 

 tologie Francaise ' does not correctly represent this species, a 

 specimen of which from the d'Orbigny Collection we have 

 had the opportunity of examining. 



Horizon. Inferior Oolite. 



Locality. Burton-Bradstock, Dorsetshire. 



12. Nautilus multiseptatusj sp. nov. 

 Fig. 13. 



Nautilus multiseptatus. — a, peripheral view of the septate part of the 

 shell, showing the sutures and " normal line ; " b, lateral view of the 

 same ; c, interior whorl of another specimen, showing the siphuncle 

 and the inner (dorsal) lobe of the sutures. Drawn from specimens 

 in the British Museum (no. 82379). a and b rather more than half 

 natural size ; c, natural size. 



Sp. char. Shell compressed at the sides and somewhat 

 flattened on the periphery, so that the whorls have a sub- 

 quadrate section. Umbilicus open, of moderate size, with 

 rather steeply sloping sides, probably exposing the inner 

 whorls, hut the specimens are not complete enough to deter- 

 mine the amount of enrolment. Septa very numerous, 

 thirteen in about half a volution ; sutures gently curved upon 

 the sides of the shell and nearly straight upon the periphery. 

 Internal (dorsal) lobe very conspicuous (see fig. 13, c) . The 

 cast is marked with a very distinct " normal line " along the 

 median line of the periphery (see fig. 13, a). Siphuncle 

 below the centre. Some detached body-chambers, probably 

 belonging to this species, have portions of the test preserved, 

 and this is quite smooth. 



Remarks. This species appears to be nearly related to 



21* 



