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GASTEROPODA OF THE INFERIOR OOLITE. 



235. Littoeina (? Trochus) pisolitica, sp. nov. Plate XXIV, fig. 9. 



Description : 



Length ..... 4 — 5 mm. 

 Length of body-whorl to total height . . 56 : 100. 



Opening of the spiral angle . . . 70°, 



Shell small, trochiform, spiral angle convex, sutures distinct. Number of 

 whorls five, apex obtuse and smooth ; remaining whorls convex, and ornamented 

 by five spirals, decussated at the nodes by axial lines which produce a subreticu- 

 late structure ; the anterior spiral slightly prominent. 



Body-whorl large, subangular, with six spirals ; base rather flattened, and 

 with about seven nearly smooth spirals. Aperture subcircular, pillar-lip very 

 short and with but little callus. 



Relations and Distribution. — Failing to recognise any corresponding adult 

 form, I am disposed to conclude that " Littorina " pisolitica is a variable micro- 

 morph, which seems to be related to species described under Littorina, but which 

 may really be a Trochus. 



Occurs in the Pea-grit at Crickley and Leckhampton. 



N.B. — The two remaining species described under Littorina are cylindro- 

 conical forms which resemble Trochus. 



236. Littoeina (? Trochus) eecteplanata, Tawney, 1873. Plate XXIV, figs. 6 



and 7. 



1873. Ltttorina eecteplanata, Tawney. Dundry Gasteropoda, p. 24 (16), 



pi. ii, fig. 6. 



Description : 



Length ..... 13—20 mm. 



Length of body- whorl to total height . . 40 : 100. 



Spiral angle .... 40°— 45°. 



Shell cylindro-conical, spire pointed. Number of whorls probably seven, flat 

 and well separated by the suture. The ornaments consist of four closely tuber- 

 culated spirals, of which the anterior is the strongest and forms a slight salience ; 

 sometimes a fifth spiral may be noted in the gape of the suture ; axial costse 

 sharply defined throughout. 



Body-whorl angular, with four or five spirals much tuberculated, the fourth 

 spiral constituting a carina at the angle ; base subconvex, with five almost plain 

 spirals. Aperture trapezoidal, with a thick columellar lip. 



