INVERTEBRATE PALAEONTOLOGY 



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obscure vertical folds, which on the angle of the last turn assume rather more 

 the character of obscure nodes: entire surface marked by raised, revolving 



lines; aperture trigonoid-oval, being biangular abov 



re ami aorupl Iv com ractei 



Fie. 50. 



below; beak, it any existed, unknown. 



Length (exclusive of the beak), about 2 inches; breadth, 0.90 inch; 



slopes of spire somewhat convex, and diverging at an angle of about 36°. 



As in other cases, where we have merely imper- 

 fect specimens of univalves, I can only, as it were, 

 balance probabilities in regard to the generic relations 

 of this species; the only specimen seen being merely 

 an internal cast, with the beak and lip broken away. 

 Some portions of the thin shell remain attached to the 

 cast, but even these are so eroded as only to show the 

 remains of revolving lines. In general appearance, it 

 resembles some species of Turris (— Pleurotoma) ; but, 

 the margin of its lip being broken and the curves of the 

 lines of growth not being traceable, it is impossible to 

 A cut. of tins species determine, without other specimens, whether or not it 



trotii the type-specimen, 



wMoh was found after the has the characteristic, slit or sinus, of the Turris group. 



plates were arranged. rr , ■ , . , i r t 



. I here is, however, something in the general torm of 

 the volutions, and the somewhat oblique direction of the node-like promi- 

 nences on the angle of the body-whorl, that suggests the probability of there 

 being a sinus in the lip, at the termination of the upper flattened, or slightly 

 concave, slope of the last turn. If it belongs to the Pleurotoma group at all, 

 however, it would most probably fall into the Surcula section. 



The strongest known reason tor doubting its relations to this genus is, 

 that just where the break of the lip intersects the angle of the body-volution, 

 there is slight projection, that looks as if it might be the commencement of 

 an expansion of the lip at that point, as in Anchura, Ajwrrhais, or some 

 allied genus. It may be that this appearance is produced by the break 

 passing through a node : hut the fact that this would require the node here 

 to be so much more prominent than any of the others on the body-volution, 

 raises a doubt in regard to the accuracy of this conclusion. If there was an 

 expansion of the lip commencing at this point, this shell would most prob- 

 ably fall into the genus Anchura^ and have to take the name Anchura Ililzi. 

 These questions, however, can only be settled by the examination of better 



Turns (Surenlti) .' Hitzi. 



