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SPINY-FINNED GROUP . 
a considerable number of both living and extinct genera, are all marine fishes, 
with a practically cosmopolitan distribution; many of them living at great depths, 
and coming under the denomination of deep-sea fishes. They are also a geologically 
ancient group, represented by a large number of generic types, both existing and 
extinct in the Chalk and other Cretaceous deposits. The only existing forms that 
frequent the higher strata of the ocean belong to the genera Holocentrum and 
Myripristis ; but even some species of the latter may descend as deep as one 
hundred and fifty fathoms. The typical genus Beryx has been taken from between 
three and four hundred fathoms; and from the small size of the eye the forms 
GROUP OF SPINE-FINNED FISHES. 
Teuthis (upper figure); Petnpheris (on the right); and Polynemus (on the left), (t nat. size.) 
known as Melamphoees must, in Dr. Gunther’s opinion, inhabit still lower levels. 
Another sign of their deep-water habits is afforded by the high development of the 
slime-secreting apparatus of these fishes. 
Of the genera that space permits of our noticing, the most peculiar is 
Monocentris, represented by a single small and rare species from the seas of Japan 
and Mauritius, and distinguished by the absence of armatures on the gill-cover, the 
large size of the scales, which are articulated together so as to form a solid 
armour, and the reduction of the ventral fins to a single long spine, and a few 
rudimental rays. The fish figured in our illustration ( Trachichthys trailli) 
represents a genus, with a few species from New Zealand and Madeira, characterised 
by the short and blunt muzzle, the prominent chin, the strong spine at the angle 
