ALARIA. 125 



The aperture is triangular, and produced in a long and slender canal, somewhat 

 more curved than in the preceding. In the figured specimen the callus of the 

 inner lip extends to the upper keel. 



Rare in the concavus- or Sowerbyi-bed of Halfway House. If a temporary- 

 name is required, I would distinguish this form as Alaeia dimidiata. 



46. Alaria pseudo-armata, Hudleston, 1884. Plate V, fig. 8. 



1884. Alaria pseudo-abmata, Hudleston. Geol. Mag., dec. iii, vol. i, p. 150, 



pi. vi, figs. 6 and 6 a. 



Description : 



Length . . . . .26 mm. 



Width of last whorl to length of shell . . 48 : 100. 



Spiral angle .... 34°. 



Shell strongly turrited. Whorls about ten; those below the apicals are 

 extremely angular, the dividing carina occurs about two-thirds down — a feature 

 which is very marked in the penultimate. Each whorl has about eight short, tuber- 

 culated costulae, which are straight and not developed in the anterior areas ; spiral 

 ornaments uncertain, apparently irregular. Body- whorl is largely developed, very 

 angular, and without costse. It carries a large median keel which supported one 

 or two immense spines. Other indications wanting. 



Relations and Distribution. — The peculiar character of the spire will serve to 

 distinguish this species from any other Alaria in the Inferior Oolite. It evidently 

 belongs to the section of unicarinate monodactyls, which carried powerful spines on 

 the keel of the body-whorl. It may also have some relationship to Al. armata, 

 M. and L., though that species is a difficult one to understand. 



Extremely rare in the Yorkshire Dogger. 



47. Alaria Lotharingioa, Schlumberger, 1864. Plate V, fig. 9. 



1864. Alaeia Lothabingica, Schlumb. Bull. Soc. Linn. Norm., vol. ix, p. 222, 



pi. vi, figs. 1 — 3. 



1867. — — — Piette, Cont. de la Pal. Franc., p. 105, 



pi. xxi. 



1873. — — — Tawney, Dundry Gasteropoda, p. 14. 



