CHAPTER XL 
PAREIOPLITA, OR MAILED-CHEEK FISHES 
wwH|HE Mailed-cheek Fishes. — The vast group of Parei- 
“hd oplite (Loricati) or mailed- enees fishes is charac- 
-*| terized by the presence of a “bony stay’ or back- 
ae directed process from the third suborbital. This 
extends backward across the cheek toward the preopercle. In 
the most generalized forms this bony stay is small and hidden 
under the skin. In more specialized forms it grows larger, 
articulates with the preopercle, and becomes rough or spinous 
at its surface, Finally, it joins the other bones to form a coat 
of mail which covers the whole head. In degenerate forms it 
is again reduced in size, finally becoming insignificant. 
The more primitive Pareioplite (mxapeia, cheek; dzdit7:, 
armed) closely resemble the Percomorphi, having the same 
fins, the same type of shoulder-girdle, and the same insertion 
of the ventral fins. In the more specialized forms the ventral 
fins remain thoracic, but almost all other parts of the anatomy 
are greatly distorted. In all cases, so far as known to the 
writer, the hypercoracoid is perforate as in the Percomorphit. 
There are numerous points of resemblance between the Czr- 
rhitide and the Scorpenide, and it is probable that the Scor- 
pemde with all the other Pareioplite sprang from some per- 
ciform stock allied to Cirrhitide and Latridide. 
Fossil mailed-cheek fishes are extremely few and throw little 
light on the origin of the group. Those belong chiefly to the 
Cottide. Lepidocottus, recorded from the Miocene and Oligo- 
cene, seems to be the earliest genus. 
The Scorpion-fishes: Scorpenide.—The vast family of Scor- 
penide, or scorpion-fishes, comprises such a variety of forms 
as almost to defy diagnosis. The more primitive types are 
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