crick: species of nautti.us feom the inferior oolite. 139 



Remarks. — This species is represented in the British 'Museum 

 Collection by the two examples— Nos. C. 4233 (i) and C. 4235 (ii)— 

 whose dimensions are given above. They are clearly not the inner 

 whorls of larger specimens, because in each fully one-third of the 

 outer whorl is occupied by the body-chamber. As will be seen from 

 the measurements given above, the specimen No. C. 4235 is slightly 

 more inflated than the example No. C. 4233 ; its periphery is also 

 more broadly rounded. These differences may possibly be of a sexual 

 character, but they are so slight that it is not at all improbable that 

 they are merely individual variations. 



Affinities and Differences. — This species appears to be allied to 

 N. lineolatus, but its peripheral margins are much less angular and its 

 whorls increase in thickness more rapidly. 



Form, and Log. — Inferior Oolite : Bradford Abbas, Dorset. 

 Mr. Buckman has examined these specimens, and is of opinion that 

 they came from the ^' co)icavi{s-zoiie (probably Jlt/perlioceras-lied), 

 Bradford Abbas." 



