168 
MALACOPTERYGII. 
ruption of the word Graveling , which is generally applied to that fish in the 
southern counties. 
The Pollan, Coregonus Pollan, Thomp., 
Is the only species of Coregonus yet found in Ireland. It occurs in 
Loughs Neagh, Erne, and Derg, probably also in Lough Corrib. 
The following notices of the pollan have already been published by 
me : — 
“ In September last (1834) a comparison of the Lough Neagh Coregonus with 
the Vendace of Lochmaben (whence I procured specimens through the kindness 
of Sir William Jardine, Bart.) proved to me that these species are distinct. 
The disagreement of the former with the Gwyniad or Coregonus of Wales, as 
described by Pennant, was at the same time very obvious ; and from the exam- 
ination of an individual of the latter species (lately favoured me by Mr. Yar- 
rell), and specimens of the Lough Neagh fish, I am fully satisfied that they are 
specifically different. 
“ From the gwyniad, the pollan or Lough Neagh Coregonus differs, — in the 
snout not being produced ; in the scales of the lateral line ; in having fewer rays 
in the anal fin, and in its position being rather more distant from the tail ; in the 
dorsal, anal, and caudal fins being of less dimensions ; and in the third ray of 
the pectoral fin being longest, the first being of the greatest length in the 
Gwyniad. 
“ From the pollan, the vendace or Lochmaben Coregonus differs so essentially, 
in its lower jaw being the longer, as well as in its being turned upwards, as to 
render further comparison unnecessary. 
“ The pollan is very uniform in size, its ordinary length being about 10 inches; 
none that I have ever seen exceeded 12. The relative length of the head to that 
of the body is as 1 to about 3| ; the depth of the body equal to the length of the 
head; the jaws equal, both occasionally furnished with a few delicate teeth; 
the tongue with many teeth : the lateral line sloping downwards for a short way 
from the operculum , and thence passing straight to the tail ; nine rows of scales 
from the dorsal fin to the lateral line, and the same number thence to the ventral 
fin ; the row of scales on the back, and that of the lateral line, not reckoned ; 
the third ray of the pectoral fin the longest. 
D. 2+12; P.16; Y. Ill; A. 2+11; C. 19; B. 9. Vertebrce 59. 
Colour to the lateral line dark blue, thence to the belly silvery; dorsal, 
anal, and caudal fins towards the extremity tinged with black ; pectoral and 
ventral fins of crystalline transparency, excepting at their extremities, which are 
faintly dotted with black. Irides silvery, pupil black. 
“ As not one of the Coregoni of which I can find descriptions agrees with the 
Lough Neagh species, I am induced to consider it as new, and venture to pro- 
pose for it the name of Coregonus pollan ,* as by this trivial appellation it is in- 
variably known in its native district.” f 
The above description of the pollan was read before the Zoological Society of 
London on the 9th of June, 1835. The following particulars 1 then looked for- 
ward to publish in a paper on the fishes generally that inhabit Lough Neagh, 
but, until this can appear, the present contribution towards the history of a spe- 
cies which is certainly distinct from the gwyniad and vendace (the only other, 
* Although the pollan accords not with any Coregonus yet described, it was 
with much hesitation that I bestowed on it a new name, being fully aware that 
the same species is often very differently described by different authors, and un- 
der the impression that it may eventually prove identical with some of the con- 
tinental Coregoni, with which I had not an opportunity of comparing it, — the ac- 
tual examination of specimens being the only true criterion by which to judge of 
such closely allied species as this genus presents. 
f Proceedings of the Zoological Society of London for 1835, p. 77. 
