~ 
Description of a new Species of Torpedo. 169 
with a few almost black dots wanes over it: precast ~ 
neath is white. 
My friend Dr. Wessel dissected the mdepotitiade organs, anit has 
furnished me with the following notes. 
The electrical organs of the 'Torpedos have already been well 
described, especially by Mr. Hunter and Mr. John Davy; and in 
the present species there exists nothing which does not sufficient- 
ly correspond with the descriptions of these anatomists. The or- 
gans in which the electricity is developed, are situated in the space 
comprised between the anterior edge of the pectoral fin and the 
cranium, the outline of which is sufficiently obvious in the plate. 
They are of a kidney shape, the concave edge being directed 
towards the bronchiw, and measure fifteen inches in length and 
eight in breadth. They consist of multitudes of triangular, quad- 
rangular and hexagonal columns, extending from the upper to the 
under surface of the body, and each column is subdivided into 
numerous cavities or cells by transverse septa, of which Mr. 
Hunter counted more than one hundred to the inch, and each 
cell is filled with a gelatinous fluid. The most remarkable pecu- 
liarity, however, is the disposition of the nerves by which the 
electrical organs are supplied, and which have undergone a devel- 
opment of which there is probably no parallel in the class of fishes. 
The fifth and eighth pairs of nerves are the electrical nerves. 
The fifth pair of nerves, B, is distributed to the anterior part of 
the head, and the anterior portion of the electrical apparatus ; and 
the eighth, C and C’, known as the vagus” ‘or branchio-gastric 
nerve, has its usual distribution to the organs of respiration, and 
the cesophagts and stomach, and in these directions its branches 
are of the usual size ; but the additional branches which go to the 
batteries, as also is the case with those of the fifth, have acquired 
a volume many times that of the spinal marrow itself, and are to 
be regarded as an index of the great activity of the organs to 
which they belong. One other peculiarity equally remarkable 
remains to be noticed, viz. the ganglia from which the posterior 
nerves, the eighth pairs, originate. By referring to the plate the 
following parts will be seen: 1. cerebral hemispheres; 2. optic 
lobes; 3. cerebellum. These constitute the brain properly speak- 
ing, and have the same relative size as in the Raiade generally ; 
but behind is a ganglionary mass (4) which exceeds the brain 
itself in bulk, and from which the electrical nerves, as will be 
Vol, xiv, No. 1.—April-June, 1843. 22 
