302 W. H. Eudleston—On the Yorkshire Oolites. 



species of Neritopsis bears it, I have ventured to restore the original 

 title. It is rather singular that D'Orbigny, who knew Neritopsis so 

 well, should have let this one pass for a Turbo. If we can judge 

 from the figure in the T. J. his specimen had undergone exactly 

 the same treatment as ours — viz. the anterior portion of the aperture 

 had been broken off. 



Description. — Specimen from the Cornbrash (zone 4), Scarborough. 

 Leckenby Collection. Lycett's type kefigured. 



The following is Lycett's description : " Shell ovate, depressed : 

 spire elevated, consisting of three or four volutions, which are 

 narrow, inflated, their sutures deeply channeled ; the last volution 

 has some obscurely marked, irregular and unequal transverse costee 

 decussated by encircling striations : the striations are regular, very 

 closely arranged, faintly impressed, with small wave-like undula- 

 tions : the aperture is large and rounded." 



Belations and Distribution. — An apical view best exhibits the 

 characters of this peculiar species, which has to a certain extent the 

 aspect of a hybrid. The delicate spiral lines with the " wave-like 

 undulations " partly remind one of Neritopsis, from which it chiefly 

 differs in the excessive fineness of the ornamentation, and somewhat 

 also in the general outline. The two specimens in the Leckenby 

 Collection and a small one in the York Museum are the only in- 

 stances of its occurrence within my cognizance. The species nearest 

 to it is one, not extremely uncommon in the Dogger, usually known 

 as Turbo l(svigatus,^ Phil. These two species seem to form a group 

 by themselves, which for the present at least, may be held to con- 

 stitute a section of Neritopsis. 



66. — Nekitopsis, species. PI. IX. Figs. 13a, lob. 



Compare — 



1862. Neritopsis Bangierana, D'Orbigny. Terr. Jurass. ii. p. 224, pi. 300, 



figs. 11-13. 

 1860. Neritopsis Guerrei, Hebert and Deslongchamps, Bull. Soc. Linn. Norm. 



vol. T. p. 185, pi. i. figs. 4«, b, c, d. 



Description. — Specimen from the Kelloway Kock (zone 5), Scar- 

 borough. Leckenby Collection. 



This is a cast, from the red-stained oolite of the Kelloway Eock, 

 28 mm. in height by 32 mm. in width. The fossil is so completely 

 skinned, that we can only guess the spiral ribbing was rather fine ; 

 it is not clear whether there was any transverse ribbing. The 

 posterior and anterior muscular scars are well shown. 



Mr. Leckenby was inclined to refer the great Neritopsis of the 

 Kelloway Rock to N. Guerrei, more perhaps because of the presumed 

 similarity of the horizon than from any marked resemblance. Strong 

 transverse ribbing is one of the features of N. Guerrei, and there is 

 no trace on the Scarborough fossil that any such existed. The 

 Leckenby specimen is exceptionally large ; there is another 

 belonging to the Scarborough Museum about half the size, in the 

 same condition, and from the same horizon and locality. Eare. 



1 To be figured and described in the next part of this Memoir. 



