200 W. H. Hudkston — On the Yorlishire Oolites. 



some synonym. It reaches a fair size in the Scarborough Limestone, 

 where the specimens are less sharply preserved, and present a more 

 softened outline than those from the Dogger. No umbilicus. 



6. — Natica adducta, Phil., var. canina. Plate V. Fig. 7. 

 1829. ?Natica adducta, Phil., G. T. pi. xi. fig. 35. 

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

 Wyke). Leckenby Collection. 



Length 20 mm. 



Width 16 ,, 



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



Spiral angle 87°. 



Proportions nearly the same as Fig. 6 ; but with a slightly smaller 

 spiral angle. The flatted portion of the whorls is narrower, and in 

 this specimen at least the channelling is less marked. Moreover, in 

 the body- whorl there is a tendency to the development of a median 

 keel, which is in marked contrast to the smooth outline of the body- 

 whorl in Fig. 6. 



The absence of an umbilicus seems to distinguish this from N. 

 Lorieri, D'Orb. (T. J. p. 190, pi. 289, figs. 6, 7). 



7. — Natioa pkoxima, sp.n. PI. V. Figs. 8a, 8h. 



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

 Wyke). Leckenby Collection. 



Length 25 millimetres. 



Width 18-5 ,, 



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



Spiral angle 75°. 



Shell oval, subumbilicate. Whorls six, regular, smooth, and slightly 

 tumid. The flat area of the upper part of the whorl is narrow, and 

 the border bevilled off, thus reducing the tabular area, so character- 

 istic of the preceding species, to a minimum. Aperture oval, and 

 rather compressed. There is a well-marked umbilical groove with 

 a very considerable callus on the inner lip. 



Fig. 9. Specimen from the Dogger. My Collection. This is too 

 much compressed for accurate measurement. The outline and pro- 

 portions are nearly the same as in Fig. 8. The umbilical groove 

 and patulous inner lip are strongly shown. As N. proxima is the 

 only species from these beds showing any considerable trace of 

 callus or of umbilicus, I venture to class this singular specimen pro- 

 visionally with tbat species. 



The peculiar state of fossilization has developed the lines of 

 growth to such an extent as to impart quite a sculpture to the 

 surface of the whorls. The age of the shell may have favoured this, 

 but the feature is, in the main, a subsequent development, and has 

 no structural significance. 



Belations and Distrihulion. — This shell, which is intermediate in 

 its spiral angle between Natica adducta and Natica punctura 

 (Bajocensis), presently to be described, has also affinities with Natica 

 canina, in a very slight tendency to a median keel in the body-whorl, 

 whilst in the strongly patulous inner lip and marked umbilical 



