lO THE DISPERSAL OF SHELLS. 



to have come together in one small pond. I will here 

 add particulars of the Lincolnshire catch-water pond 

 referred to, and of one or two other isolated ponds, &c. 

 Details, in such cases, must always be tedious, but the 

 subject, as it seems to me, is an interesting one. 



Pond at Welton-le- Wold, Lincolnshire. — A small 

 pond, about nine yards in length, on the Wolds not far 

 from Louth, near the crown of Bunker's Hill. A great 

 distance from any other water, and far above the 

 nearest stream. Between arable fields, but with no 

 ditches near. Probably old, having existed, perhaps 

 when the wold was unenclosed ; remains of a rough 

 pump are to be seen on one of the banks. Water 

 derived solely from rain, &c., failing in the immediate 

 neighbourhood. No water-weeds are likely to have 

 been planted by man. Four species of shells occur : 

 SphcBvinm lacustre, Pisidium ptis ilium, Limncea peregra^ 

 and Limncea truncaiula. 



Pond at RiplingJiani, Yorkshire. — Mr. F. W. Fierke, 

 of Hull, has favoured me with particulars of a somewhat 

 similar pond on the Yorkshire Wolds, at Riplingham, 

 scooped out of the chalk and laid over with clay, and 

 supplied with water by rain and surface drainage only. 

 The ever present Liinnoea peregra^ among higher 

 organisms seemingly the only inhabitant, exists in 

 countless numbers, almost covering the bottom. There 

 are no water-weeds. Many ponds of this kind. 



' Specimens were exhibited at the Conchological Society on 

 7th October, 1S91 ; see '* Journ. of Conch.,'' vi. (1891), 398. 



