W. S. Hudleston — On the Yorkshire Oolites. 199 



indications whicli serve to connect tlie 2nd zone of tlie Yorkshire 

 Inferior Oolite with the Lincolnshire Limestone, and this again 

 would seem to be somewhere about the horizon of the Oolite Marl 

 of the Cotteswolds, where also N. cincta is abundant and of good 

 size. Instead of a fossil, which was supposed {vid. supra) to range 

 from I. 0. through G. 0. into C 0., the larger forms are confined to 

 one limited horizon in the I. 0. throughout England north of the 

 Avon ; the finest specimens, with the shell on, coming from Combe 

 Hill near Deddington (North Oxfordshire), where it occurs along 

 with Am. MurchisoncB, Terebratula fimbria and Spiropora straminea 

 (the original Millepore).' There are no signs of it in the Anglo- 

 Norman basin that have come under my notice, nor anywhere on the 

 Continent. 



5.— Natioa adducta, Phillips, 1829. Plate V. Fig. 6. 



1829, 1835. JSTatica adducta, PML, G. T. pi. ix. fig. 30. 



1850. JSTatica adducta, Phil., Morris and Lycett, Gt. Ool. Moll. p. 112, pi. xv. figs. 



17, 17«. 

 1852 ? JSr. adducta, PhU., D'Orb. T. J. p. 189, pi. 289, figs. 4 and 5. 



Bibliography, etc. — The history of this rather common species has 

 been slightly complicated, from the fact that Phillips gives two very 

 different figures of " Naiica adducta," viz. pi. ix, fig. 30, and pi. xi, 

 fig. 35. The former is from the Scarborough Limestone (zone 3), 

 the latter from the Dogger (zone 1). They look very different, but 

 since Morris and Lycett refigure the specimen from the Scarborough 

 Limestone as the type, it may be as well to regard it in that light. 

 This form is not rare in all three zones of the Inferior Oolite of 

 Yorkshire. Although D'Orbigny refers to Phillips's pi. xi. fig. 35, 

 his own figures are more like the form one usually finds, and which 

 is figured in the accompanying Plate. 



Description. — Specimen from the Dogger (zone 1) Peak (Blue 

 Wyke). Collection of the Scarborough Phil. Soc. 



Length 23 mm. 



Width 19 ,, 



Eatio of body-whorl to entire shell .... 70 : 100. 

 Spiral angle 92°. 



Shell somewhat longer than wide ; oval, not umbilicated. This 

 specimen, of which the spire is unusually well and sharply preserved, 

 has six whorls, which increase moderately and regularly with a 

 sutural angle of very slight inclination. Upper part of each whorl 

 flatted, and very slightly channelled ; sides of the whorl steep and 

 very slightly convex. The general contour regalar and slightly 

 angular. Lines of growth broad and fairly preserved. No punct^ 

 visible. 



Relations and Distribution. — The very singular manner in which 

 many of these Naticas run into each other, when one looks over a 

 large series, leads one to suppose that more names may have been 

 given than the necessity of the case requires. This appears to be a 

 very average form, and with very slight differences has a wide 

 range ; possibly, as far as lists go, its presence may be masked under 

 1 Judd, Geology of Kutland, p. 25. 



