GASTEROPODA. 45 



N. Testa hemispharicd, spird j)arvd, depressd ; apice acuto ; anfractibus angustatis, 

 planis, anfractu ultimo ventricoso ; aperturd ellipticd. 



Shell hemispherical, spire small, depressed; the apex acute; whorls narrow and 

 flattened, the last whorl ventricose ; aperture of moderate size, and elliptical ; inner lip 

 rounded. 



The general figure approaches to globular, except at the base of the spire, which is 

 flattened, and only the small volutions rise above the wide and flattened upper surface of 

 the last whorl ; the base is comparatively narrow ; the inner lip is gracefully curved, but 

 not apparently thickened, nor is there any trace of an umbilical fissure. One specimen only 

 was obtained in the planking. It is imperfect about the outer lip, and scarcely half the 

 dimensions of the shell figured by D'Archiac. Length 10 lines, breadth 10 lines. 



Locality. Minchinhampton ; Eparcy, France. 



Sub-Genus EUSPIRA, Ag. 



Shell smooth, ovate ; spire elevated ; of few whorls, which are angulated, the angles 

 sometimes taking the form of a carina ; less frequently the last whorl has a second carina, 

 or the carina becomes nodulous or tuberculated ; aperture entire, elliptical, modified by the 

 angle of the whorl ; base wide, rounded ; pillar lip smooth and excavated, outer lip thin 

 and smooth. 



The Great Oolite shells referable to this genus are all rare. One of them, however 

 (E. canaliculatd], though rare in this formation, is abundant in the middle division of the 

 Inferior Oolite. 



EUSPIRA CANALICULATA.* Plate XI, fig. 23, 23a. 



E. Testa oblongd, spird sub-exsertd, apicc. acuto, anfractibus anffulosis, angulis acutis; 

 anfractibus superne profunde canaliculatis, inferne sub-convcxis ; anfractu ultimo obliquo, 

 basi attenuatd; apcrlurd ellipticd, fssurd umbilici anyustatd. 



Shell oblong, spire but little elevated, apex acute, whorls angulated, the angles acute, 

 the upper portion of the whorls deeply channelled, their lower portions rather convex, the 

 last whorl oblique, its base attenuated ; aperture elliptical, the umbilical fissure narrow. 

 Several obscure encircling lines may be traced upon the middle of the last whorl. The 

 specific characters of this shell are so strongly marked that it will not readily be mistaken 

 for any other; several specimens have been extracted from the limestone beds in the upper 

 portion of the Great Oolite ; but in the middle bods of the Inferior Oolite in Gloucester- 



1 Although we have provisionally arranged this and the four following species under a sub-genus of 

 Natica, they present considerable affinities to the Palaeozoic genus, Scalites (Hall), in the lines of growth 

 having the appearance of a slight fissure where the angle occurs m the volution. 



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