PLATE Lift. 
lialf as broad at the posterior extremity. Each consists wholly of 
perpendicular columns, reaching from the upper to the under surface 
of the body, and varying in their lengths, according to the thickness 
of the parts of the body where they are placed ; the longest column 
being about an inch and a half, and the shortest about one fourth of 
an inch in length, and their diameters about two tenths of an inch. 
The figures of these columns are very irregular, varying according 
to the situation and other circumstances. The greatest number of 
them are either irregular hexagons, or irregular pentagons; but 
from the irregularity of some of them, it happens, that a pretty 
regular quadrangular column is sometimes formed. Those of the 
exterior row, are either quadrangular, or hexagonal, having one 
side external, two lateral, and either one or two internal. In the 
second row, they are mostly pentagons. Their coats are very thin, 
and seem transparent, closely connected with each other, having a 
kind of loose net-work of tendinous fibres, passing transversely and 
obliquely between the columns, and uniting them more firmly to- 
gether. These are most observable, where the large trunks of the 
nerves pass. The columns are also attached by strong inelastic 
fibres, passing directly from the one to the other. The number of 
columns in different Torpedos of rather small size, appears to be 
about 470 in each organ, but the number varies according to the 
size of the fish ; and in a very large Torpedo, the number of co- 
lumns in one electric organ was 1182. They must therefore in- 
crease, not only in size, but in number, during the growth of the 
animal, new ones forming perhaps every year on the exterior edges* 
as they are the smallest. This process may be similar to the forma- 
tion of new teeth in the human jaw, as it increases. Each column 
is divided by horizontal partitions, placed over each other at very 
small distances, and forming numerous insterstices, which appear to 
