134 



LAND AND FRESHWATER SHELLS IN THE 

 NEIGHBOURHOOD OF WHITBY. 



H. POLLARD, 

 Late Secretary y Leeds Xaturalists C.V/c/. 



The AVhitby district affords an interesting and wide field of investi- 

 gation to the conchologist. It consists of the valley of the Esk, a 

 considerable amount of moorland, imdercliff, beach and scaur. 

 Of these the undercliffs have as yet yielded the largest number of 

 species. In the valley of the Esk there appears to be a scarcity of 

 moUuscan life, and in the Esk itself up to the present time, the only 

 valuable species occurring is the Pearl ]\Iussel { Unio viargaritifer^^ 

 and its variety simiata. The moorlands, also — and this is probably 

 on account of their geological formation and physical features —seem 

 to contain but a very limited number of species, and those of the 

 commonest type and ordinary occurrence. The undercliffs, on the 

 contrary, are rich in conchological treasures. The species, however, 

 are, as a rule, very small in character, and require much care and 

 patience in the collection of them. 



Regarding the conchology of the beach and scaur, no comment is 

 here made, the specimens being marine, and not coming within the 

 range of the paper. 



The most important mollusc yet collected in the Whitby district 

 is the variety alba of Bulimus obscuriis, which was secured in 1879^ 

 amongst hedgerow type specimens, in the Factory Fields, which lie 

 to the right in ascending Bagdale. The record is but the second for 

 Yorkshire, it having in the first instance been taken twelve years 

 previously at Grimbald Crag, near Knaresborough, by Mr. Becvers. 

 The occurrence of this variety so unexpectedly, and in such an 

 unlikely locality, shows that no place should be despised or over- 

 looked in collecting. The records of shells given in this list are 

 all that have to date been made public, so if any collector is able to 

 supplement them, his notes will be of much value and interest. To 

 avoid the repetition of any record, the earliest known is inserted, all 

 those subsequent being omitted. 



The initials Y.N.U. refer to an excursion of the Yorkshire 

 Naturalists' Union, which took place on August 3rd, 1885, and 

 m which the Rev. W. C. Hey, Messrs. Baker Hudson, William 

 Coates, and W. Denison Roebuck represented the conchological 

 section ; the excursion being reported in the Naturalist for October 

 1885, p. 348. 



Naturalist, 



