Nigerian Eocene Mollusca. 25 



spire of widely conical and pagoda-like shape is composed of three smooth, 

 elevated, embryonic whorls with an obtuse nucleus, while the succeeding whorls 

 have a depresso-concave surface, furnished with a microscopically fine reticulate 

 sculpture caused by the delicate spiral striations being crossed by longitudinal 

 lineations which are deeply sinuated. Minute equi-distant tubercles ornament 

 the sutural margins, while the sculpture of the body-whorl is somewhat 

 coarsely reticulate, the spiral costae being well pronounced and bearing regular 

 tubercles at the junctions with the longitudinal striations. It is in some of these 

 details that the Nigerian shells agree with C. parisiensis, although the latter 

 has a less pagodiform spire and an ornamentation on the body-whorl which is 

 much less accentuated, a difference, however, which may be due to erosion. 



DISTRIBUTION. Middle and Upper Eocene of Europe. 

 OCCURRENCE. Cuttings Nos. i, 5, 6, 10, n, 12, 14, 15. 

 COLLECTOR. Mr. Kitson. 



Family VOLUTID^E. 

 Athleta lugardi, sp. nov. 

 PLATE 5, figs. 1-3. 



DESCRIPTION. Shell elongate, laterally sloping, widely coniform, robust, 

 spire short, spreading, depresso-convex, comprising seven whorls divided by 

 a rather irregular, linear or slightly canaliculate suture ; body-whorl flattened 

 and wide above, obtusely angulate at shoulder, laterally oblique, about five-sixths 

 higher than the spire, anteriorly twisted and broadly notched at base ; aperture 

 bi-canaliculated, narrowly oval, slightly oblique ; columella evenly excavated, its 

 basal part flattened and tapering, having a wide callosity which is very elevated, 

 and thickened posteriorly, bearing well within one or two obscure, oblique 

 plications succeeded by a twisted curvature at the basal extremity ; parallel 

 with the outer lateral margin of the columella lies a long, wide, funiculate growth, 

 the " bourrelet " of French authors, which forms a closely twisted lamellate 

 structure, ending in a broadly excavated notch of the short and wide canal, 

 between the " bourrelet " and the columella, is a narrow umbilical slit ; labrum, 

 slightly sinuous, not dilated, thin, smooth within, rounded at the anterior corner, 

 in rear obtusely angled, thickened, widely excavated and channelled ; surface 



