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about an inch in breadth round the pectorals, but narrower on the ventrals, and 
still more so on the tail. 
“To recapitulate — in all the works noticed in this communication, and perhaps 
unnecessarily so, the only figures of the torpedo corresponding exactly in propor- 
tion with my specimen are Walsh’s,* which are copied by Pennant. Those of 
the Tremola , illustrative of Dr. Davy’s memoir, seem much the same. Two 
desirable points are however attained — the identity of the species with Walsh’s 
specimens from the coasts of France and England, and the description of an 
authentic native example of the fish. From Dr. Jacob I learn that two torpedos 
were taken at the same time, about ten years ago, and he thinks off Dublin Bay, 
like the present individual ; of one of these there is a cast in the Museum of the 
College of Surgeons in Dublin ; f this I have examined ; it is 38 inches in length, 
28 in breadth, and represents the same species as the subject of the present com- 
munication.” 
A torpedo taken by the Dublin fishermen, which weighed 14f lbs., 
was described by Mr. M‘Coy, in the 6th vol. Ann. N. H. as a new 
sp., under the name of T. emarginata. A figure of it accompanies the 
description, and appears very different in form from other torpedos taken 
on the coast. Dr. Ball, however, who saw the specimen in a recent state, 
is decidedly of opinion that it is not distinct in sp. from the others. That 
gentleman, having obtained a specimen taken off the Dublin coast on the 
1st Sept., 1840, remarked, in a letter to me, that he felt convinced the 
specimen described by me and the T. emarginata , and also the one re- 
cently received, were identically the same sp., and adds, “ I found that 
the slightest pressure at each side of the head was sufficient to make a 
shrugging of the shoulders, if I may so express it ; or, perhaps more pro- 
perly, to flex the joints of the cartilaginous arch, which supports the 
exterior of the lateral expansions or fins : this flexure produces the two 
indentations so obvious in the specimen described by Mr. M‘Coy, while at 
the same time the edge all round is drawn in and thickened. Did the 
fish die in a state of spasm, it would, I think, present the form under 
which it has been named T. emarginata , while in its ordinary flaccid state 
it is T. Walshii. The slight difference of position of the dorsal fin, if not 
the result of irregularity produced in the drying of the skin, may probably 
be also an effect of the same cause as that which produces the indenta- 
tions and the thickening of the edges of the fish. I did not however look 
to this point.” J 
In describing Dr. Jacob’s torpedo, in the 5th vol. of the Annals, I gave it 
as my opinion, that it was identical with Walsh’s, the only difference worthy 
of note between my specimen and his figure being that the spiracles in the 
latter are represented as notched , and, for the sake of identification, I sub- 
sequently proposed, in my Report on the Fauna of Ireland, to name the 
Irish specimens T. Walshii , in the then confused state of the genus. At 
that time I was not aware of the T. nobiliana of the Fauna Italica. With 
* I do not recollect to have seen it anywhere satisfactorily stated, whether 
individuals of the same species differ much in general outline, or whether the 
sexes ever vary much in this respect — colour is admitted to be no character. 
See in particular Dr. Davy, Phil. Trans. 1. c. 
f Dr. R. Ball has an excellent cast from the present specimen. 
X Dr. Ball has since confirmed his views, and ascertained that the form, wdiich 
not unnaturally led Professor M‘Coy to consider the specimen he describes as a 
new species, originated in its having been tied up in a handkerchief, by fisher- 
men anxious to prevent injury. Dr. Ball, having received a specimen so treated, 
made a cast of it, and made another when the fish became flaccid — and thus ob- 
tained the two forms from one specimen. 
