part: the outline of each operculum is fomewhat 
finuated by two very Ihort and fubacute proceftes 
towards the middle ; and the remainder iscompofed 
of five or fix longitudinal rough-edged lamellte re- 
fembling the furface of the body. The membrana 
branchiojiega has about eight rays, of which the four 
lowermoft are rough-edged, and thicker than the 
reft. Perhaps no filh yet known, if we except what 
are called mailed or cataphradted fifti, is fo ftrongly 
coated as the prefent; the fcales forming a kind of 
proceftes, which are fo ftrongly and clofely inferred, 
that it is not poflible by means of a forceps to detach 
one from the reft, without bringing aivay with it a 
fmall portion of the corium or general integument 
itfelf; the fkin in this refpedt refembling in fome 
degree that of the genus Balijles. Thefe fcales or 
proceftes, as to their general ftrudture, are analogous 
to thofe of the Chsetodons ; terminating outwardly 
in a fringe of fmall, ftrong fpines, befidcs feveral 
fcattered ones on the furface. They differ fomewhat 
in ftrape on different parts of the animal, and, as 
they approach the abdomen, become more dilated. 
The abdomen itfelf is carinated and cataphradted by 
a row of eight ftrong, rough incifures or fcales, each 
of which proje<fts into a ftiortiih fpine, pointing 
backwards, and forming a ftiarp keel beneath, while 
the fides are continued upwards near a quarter of an 
inch on each fide the abdomen. The fcales of the 
abdomen, as before obferved, are alfo fomew'hat 
broader in this part, and gradually leffen towards 
the middle of the body. On each fide the tail is a 
ftightly-prominent line, or an approach to a carinated 
appearance, 
