EXELTSSA. 179 



Eparcy ; the apex also is somewhat more obtuse. The ribs are wider apart, the 

 last whorl somewhat less constricted, and the aperture less filled up, and not 

 quite so circular. There are eight costae, which are decussated by about as many 

 fine spiral lines. This variety differs from the type exactly in the opposite direc- 

 tion to Ex. pisolitica, but is, on the whole, nearer to the Great-Oolite forms. 



Rare in the Lincolnshire Limestone of Weldon, where poorly preserved speci- 

 mens are difficult to distinguish from bad specimens of Cerithium subcostigerum. 



108. Exelissa pulchra, Lycett, 1863. Plate XI, fig. 7. 



1863. Kilyeetia pulchea, Lycett. Suppl., pp. 10 and 91, pi. xliv, fig. 4. 



The following is Lycett's description : " Shell small, thick, elongately turrited 

 (?) ; volutions eight, convex, the sutures deeply impressed ; transverse {%. e. 

 axial) costse about twelve in each volution, oblique, large, decussated, and 

 rendered nodulous by six narrow encircling lines ; . . . . the figure of the 

 aperture in shells of the same size presents some variability, the typical sub- 

 orbicular figure becomes subquadrate, and in other instances is somewhat pointed 

 at the two extremities, but in the young condition apparently the aperture is 

 always orbicular." 



As I have not had an opportunity of seeing specimens of Ex. pulchra either 

 from the Great Oolite of Minchinhampton or from the Forest Marble of Laycock, 

 there may be room for doubting the present identification. But certain shells 

 from the Lincolnshire Limestone at Ponton answer very well to Lycett's figure and 

 description. This case affords another instance of the resemblance in Ponton 

 fossils to Bathonian forms. 



109. Exelissa "Weldonis, Hudleston — Correction of name. Plate XI, figs. 8 a, 8 b. 



1884. Ceeithium (Kiltektia) Couptonense, Hudl. Geol. Mag., dec. iii, vol. i, 



p. 62, pi. iii, fig. 14. 



Bibliography, 8fc. — By inadvertence this species, so characteristic of the 

 Lincolnshire Limestone of Weldon, received the specific name of " Comptonense." 



Description. — Length about 6 mm., width less than one-third of the length. 

 Shell pupaeform ; whorls six to eight, sutures not very distinct in the spire. The 

 ornaments are more conspicuous spirally than longitudinally. In the majority of 

 specimens are three spirals, the upper and lower of which, but sometimes all three, 



