114 WAITE : VERTEBRATES OF THE WESTERN AINSTY. 
in numbers is mainly attributable to the pollution poured into 
the river from the Otley paper mills. The Wharfe within the 
district is becoming more a Grayling than a Trout stream 
(J. Heart, ‘Field,’ Oct. 13th, 1888, p. 5§37.).. But Mr. J. N. 
Walbran, of Leeds, tells me that the Trout is the commoner fish 
in the higher reaches of the river, e.g., about Burnsall. This fish 
is far from common in the Nidd. 
Thymallus vulgaris Nilss. Grayling. Very common in the 
Wharfe, where it appears to be increasing in numbers. It is 
always caught more plentifully during winter. The Grayling 
is also found in the Nidd, but is not nearly so common. 
Clupea alosa Linn. Allis Shad. In Denny’s catalogue before 
referred to, the author writes:—‘I purchased a specimen of 
this fish in the (Leeds) Market for our Museum, which was 
said to have been taken at Tadcaster.’ 
Anguilla vulgaris Flem. Sharp-nosed Eel. Locally called 
Silver Eel and Snig. Abundant in the Wharfe, but more so in 
the Nidd, which isa slower-moving stream. 
A common method of catching Eels is to thread a few score 
of dew worms on to a piece of worsted ; the whole is twisted 
into a mass and sunk in the river, at a spot where Eels are 
numerous. After a while a landing-net is placed carefully 
beneath the mass, and the fish, having swallowed the worms, are 
sometimes caught in very large numbers. 
Anguilla latirostris Risso. Broad-nosed Eel. Local name, 
Black Eel. Common in both the Nidd and the Wharfe, but 
not nearly so abundant as 4. vulgaris. 
Petromyzon fluviatilis Linn. Lampern. The River-Lamprey 
is plentiful in both the Nidd and the Wharfe. 
In preparing the foregoing Lists, and especially that relating to 
the Birds, I have to acknowledge much kind assistance rendered by 
the Rev. J. W. Chaloner, of Newton Kyme, and Mr. John Harrison, 
of Wilstrop Hall, whose acquaintance with their own districts has 
been seventy years and forty years respectively. I am indebted 
to my friends Messrs. Wm. Eagle Clarke and Wm. Denison Roebuck 
for access to a large amount of published records and to manuscripts 
by the late John Tennant and Wm. J. Milligan, which have enabled 
me to complete the bibliography of the district. I take this 
opportunity of thanking Mrs. Hatfeild, of Thorp Arch Hall, for 
granting me every facility for the investigation of her estate ; and 
also to Mr. J. Lloyd Wharton, M.P., of Bramham, for permitting 
research on his game preserves in the Walton district. ame 
Naturalist, 
