NATICA. 81 



Natica chauviniana, D'Orb. Plate VIII, fig. 6. 



1852. Natica chauviniana, D'Orbigny, Pal. Franc. Terr. Jurassiques, p. 198, pi. ccxci, figs. 12, 13. 



Type. — " Spiral angle 104°. Length 35 mm. Breadth 29 mm. An interior 

 mould a little longer than broad, oval. Spire short, formed with a very convex 

 angle, composed of short convex whorls of which the last is twice the size of the 

 others. Mouth oval." From the Callovian of Sarthe. 



Description. — The specimen referred to this species has a spiral angle of 84°. 

 The breadth is 0'9 of the length. Of this length the last whorl is 0*75, making 

 the breadth of the last whorl 1*2 of its length. It is a cast or mould, the top of 

 the whorls forming a narrow border or ledge. The surface is convex and there 

 are four or five whorls. The remains of the umbilicus form a deep round pit. 



Distribution. — Only one full-grown specimen has been seen from Bedford, but 

 the little specimen from Bothenhampton would probably grow up into it, and the 

 species may therefore be more widely spread than appears. 



Relations. — Our specimen has not so wide a spiral angle as the type — but it 

 has a wide one, and the other proportions agree. It is remarkable for the great 

 width and short length of its body whorl. If we look through the many figures 

 given by D'Orbigny, it is remarkable that the only one which approximates to this 

 should belong to a suitable horizon. 



Natica sp. {<■/. cincta). Plate VIII, fig. 7. 



A single cast obtained from the Cornbrash at Holwell is of so suggestive 

 a character that, in spite of its not being in a fit condition to name, it requires 

 notice. It cannot belong to any of the above described Naticae, though, being 

 made of separated whorls, the shell must have been thick and not easily destroyed. 

 The matrix and the cast are almost inseparable, so that we may conclude that it 

 was a cast before it was imbedded. In other words, it is a remanie fossil, and 

 we must look in older spots for its original home. It is a large shell which yields 

 (probably) abundant casts. Exactly such a cast is figured by Hudleston (' Gast. 

 Inf. Ool.,' pi. xxi, fig. 3), as belonging to Natica cincta — a shell which, though 

 not recorded from the Inferior Oolite of Dorset, is abundant in the not remote 

 district of Gloucestershire. It would be curious if a shell excluded from a 

 district at the time of its flourishing should be introduced into it in later times 

 as a remanie, but it is not impossible, 



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