﻿1861.] 



KIRKBY PERMIAN", SOUTH YORKSHIRE. 



297 



ference is one of distribution, similar to the differences seen in the 

 distribution of marine life in recent seas — the bottoms of which, we 

 know, offer many examples of great irregularities in the distribution 

 of the various forms of life that people them. To conclude, we have 

 the Bunter Schiefer of Yorkshire apparently parallelized by some 

 obscure and little-understood beds of red sandstone which occur in 

 the south-east portion of the county of Durham, superior to the 

 upper limestone, and which have been classed by Mr. Howse * as 

 Permian under the name of Lower Bunter. 



In arriving at these conclusions I have chiefly been guided by the 

 relative positions of the subdivisions of each series. Indeed, in this 

 instance, with such differences in the pakeontological and structural 

 features of the subdivisions, vertical position is almost the only test 

 that can be used in attempting to parallelize them ; and in series of 

 strata, or rather in portions of the same series so little apart as the 

 two compared, vertical position would seem to be as good a test as 

 any that could be used. I would also observe that, in regarding 

 subdivisions to be equivalents, I also consider them to be of con- 

 temporaneous deposition. Thus the Brotherton Beds and Upper 

 Limestone not only represent the last deposition of calcareous sedi- 

 ment in each area during the Permian era, but are looked upon as 

 contemporary. It is not, of course, supposed that the accumulation 

 of each commenced and ceased at exactly the same periods in both 

 areas, but that the bulk of each subdivision was synchronously 

 deposited. [See the Tabular View of the Permian Strata of Durham 

 and South Yorkshire, p. 298]. 



§ V. Remarks on the Fossils. — I now proceed to notice the species 

 I have met with in this district. 



Cephalopoda. 



1. Nautilus Freieslebeni, Geinitz, Neues Jahrbueh, p. 637, pi. 11. 



fig. 1. 



Syhs. J¥. Eowerbanlcianus, King; and N. Theobalcli, Geinitz. 



A cast of a body-chamber of a young individual of this species 

 occurred at Brodsworth. It is rather less than half-an-inch long, is 

 a little more compressed medianly than Durham specimens of simi- 

 lar age, and shows traces of a shallow median sulcation. 



This is the only Cephalopod I have met with in Yorkshire ; but 

 Prof. King quotes it from Aldfielcl, Yorks. (in the cabinet of Prof. 

 Phillips)!. 



Gasteropoda. 



2. Turbo heliclnus, Schlotheim, Petrefactenkunde, p. 161. 



Syns. Turbo Mancuniensis, T. minutus, and Rissoa obtusa, Brown ; 

 Littorina Tunstallensis, Howse ; and Turbo Thomsonianus, 

 King. 



Full-grown specimens of this species in Yorkshire have five whorls, 

 and are about one-sixth or one-fifth of an inch in length. At Ham- 



* Ann. and Mag. Nat. Hist., 2nd ser. vol. xix. p. 34. 

 t Mon. Perm. Foss. of England, p. 220. 



