49 



THE LAND AND FRESHWATER MOLLUSCA OF THE 



DISTRICT BETWEEN ASHTON-UNDER-LYNE 



AND OLDHAM. 



By FRED. TAYLOR. 



(Read before the Society, December Sth, 1897). 



This district is a long narrow slip of country through the whole length 

 of which flows the river Medlock, one of the main sewers of Oldham. 

 It is hemmed in by the cotton-spinning towns of Ashton-under-Lyne, 

 Oldham, and Mossley, with their adjoining townships, and is probably 

 the smokiest district in the kingdom. From the main valley, branch 

 off several smaller valleys, the most important one being Holden 

 Clough ; these valleys are scantily clothed with trees and other vege- 

 tation, which is rapidly dying off (even the nettle being now a rare 

 plant), and exposing the ground to the weather ; the woods are now 

 series of landslips and swampy places. 



At first sight this district appears to be a very poor conchological 

 ground indeed, the carboniferous shales, the heavy clayey soils, and 

 the scanty herbage, are certainly not conducive to the full develop- 

 ment of the land mollusca ; but on a close search we find a few very 

 interesting and uncommon forms of the smaller species, especially of 

 the genus Hyalinia. 



On the higher parts of the district occur numerous ponds and 

 ditches, which are almost choked with an abundance of vegetation ; 

 from these we take a number of the water-loving species, and from a 

 short length of canal at Bardsley, in the centre of the district, we reap 

 an abundant harvest. 



The part of the district worked most thoroughly for land species is 

 a portion of Holden Clough, the whole length of the valley from Old- 

 ham Park through Parkbridge, Bardsley, and Riversvale, to Daisy 

 Nook ; and for freshwater species, Fitton Hill, Parkbridge, and the 

 canal at Bardsley. 



This list is not given as a complete one, for owing to the rough 

 nature of the ground it is a most difficult district to work. 



Arion ater (L.) — Very common throughout the district, the only 

 variations noticed being the var. bninnea, and a form approaching 

 var. pallescens. 



A. subfuscus (Drap.) — Occasionally met with on the canal-bank 

 at Bardsley, in the wood below the canal, and at Riversvale a light- 

 coloured form commonly occurs. 



A. hortensis (Fer.) — Abundant throughout the district 



