306 PERMIAN FOSSILS. 



volutions separated by a channelled suture ; body provided with many prominent, 

 spiral ribs ; three on the body above, with five or six concentric ones beneath, and two 

 on each of the volutions of the spire ; these are crossed by numerous longitudinal 

 wrinkles ; aperture large, orbicular ; outer lip expanded, smooth ; pillar lip with an 

 oblong umbilicus behind it. Length upwards of a quarter of an inch ; body nearly the 

 same in diameter." ( Brown .^) 



A small species, possessing some resemblance to the last, but differing from it in 

 having the spire more acuminated, the whorls less tumid, and the spiral ridges generally 

 stronger and more numerous ; the ridges range from six to nine in number. It appears 

 to have been ornamented with longitudinal coloured bands parallel to the incremental 

 laminae, which are rather prominent. 



Young specimens are somewhat umbilicated. My largest specimen is five six- 

 teenths of an inch in height, and four sixteenths in width. 



Turho Mancuniensis occurs in the Shell-limestone at Tunstall Hill ; in the Breccia 

 at the north end of Black Hall rocks ; and in the Permian Marls at Newtown near 

 Manchester, though considerably smaller in this locality than in the two former. 

 Probably it occurs in the pisolitic Yellow Limestone between Marr and Hickleton.^ 



Turbo Permianus, Kin^. Plate XVI, fig. 16. 



Turbo Permianus, King. Catalogue, p. 13, 1848. 



Diagnosis. --' Spires four, smooth, length under a quarter of an inch."^ ' Aperture 

 orbicular : inner lip slightly reflected. 



A species, generally agreeing with the above description, but occasionally exhibiting 

 several faint spiral striae, has occurred to me in various localities. My largest 

 specimen is four sixteenths of an inch in height, and three sixteenths in width. 



Professor Phillips cites Hawthorn Hive as a locality for this small species : it 

 occurred to me at Silksworth, Byers's Quarry, Humbleton, Tunstall Hill, and Hylton 

 North Farm. Fossils probably identical with it are rarely found in the Blue Lime- 

 stone of Polterton and Bolsover; and in the lower beds of Yellow Limestone near 

 Conisborough. (Sedgwick.) 



Turbo Thomsonianus,* Kin(/. Plate XVI, figs. 23, 24. 



Turbo Thomsonianus, King. Catalogue, p. 13, 1848. 



LiTTORiNA TuNSTALLENsis, Howse. Trans. T. N. F. C, vol. i, p. 240, 1848. 



1 Transactions of the Manchester Geologic^ Society, vol. i, p. 29. 



2 Vide Sedgwick, Trans. Geol. Soc. Lend., 2d series, vol. iii, p. 118. 



3 Phillips, Trans. Geol. Soc. London, 2d series, vol. iii, p. 118. 



* Named after the late Dr. Thomas Thomson, F.R.S., author of 'A Geognostical Sketch of the Counties 

 of Northumberland, Durham, and part of Cumberland," in the Annals of Philosophy, vol. iv, 1814. 



