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MALACOPTERYGII. 
employment to myriads of industrious people, 
and the fountains of commercial wealth to towns, 
districts, and even nations ; of these we shall have 
to speak somewhat in detail. 
In general there is hut one dorsal fin present in 
this Order: some of the Cods indeed are described 
as having three, but we rather incline to consider 
these as divisions produced by interruptions of 
continuity in one lengthened fin; just as the 
finlets in the typical Mackerels are structurally 
nothing more than the posterior portions of the 
second dorsal and anal cut into notches. The 
Salmons have a minute second dorsal, commonly 
called the adipose; but it is not a true fin in 
structure, being only a lamina of fat inclosed in 
a fold of skin, quite destitute of rays. 
The most singular aberrations of form and 
function that we meet with in this Order are 
found in the Flying-fishes, and in the Flat-fishes. 
The former, by an enormous development of 
some of their fins, are able to take long flights 
through the air like birds : the latter have a most 
remarkable contortion of the body, whereby the 
usual symmetry of form and organs and colour is 
lost. Both of these peculiarities will require 
special notice in their proper order. The large 
Family of the Eels also presents interesting pecu- 
liarities. 
As in the Acanthopterygian Order, we give 
from the Prince of Canino’s Synopsis a list of the 
twelve Families included in the Malacopterygii, 
with the number of species included by him in 
each Family, at the time (1831) when it was pub- 
lished. As we go through the Families in course, 
we shall mention the number of species assigned 
