| BONY FISHES. ORDER VI. THE SUN-FISH. 207 
up like a balloon, by filling with air a thin, membranous sac, which adheres 
to the peritoneum, the whole length of the abdomen. When thus inflated, 
it rolls over, and floats with belly uppermost. The length of this species 
is about nine inches. The color on the upper part of the body is yellowish- 
white, with innumerable minute black spots. The abdomen is white. 
OrtHacoriscus. — The Sun-fish has the body compressed, spineless, and 
incapable of inflation. 
O. Mola. — The Short Sun-fish. This is rather a rare fish in our waters. 
Dr. Storer gives the following description of one harpooned in Boston 
Bay : — 
“The body is oval; its whole surface a fine, unyielding, granulated cuti- 
cle, covered with a thick, adhesive mucous; back dark gray. Abdomen 
nearly white; the right side of the body rather darker than the left; both 
sides of a dirty-white color, with silvery reflections. Length, fifty-four 
inches ; depth across, from the middle of the pectorals, two and a half’ feet ; 
from the top of the dorsal to the extremity of the anal fin, six and a half 
feet. Weight, about two hundred pounds. Length of the head, from the 
tip of the snout to the base of the pectoral fin, seventeen inches ; flattened 
over the snout, which is obtuse, and projecting about an inch in front of the 
upper jaw. Eyes rather large, convex, very movable in their orbits ; pupils 
black ; irides a dark brown, encircled within by a silvery ring. Nostrils 
double, just in front of the eyes. Mouth small. Jaws armed with a 
broad, bony plate, sharp at the edges. Upon the top of the head, an 
arched ridge commences on a line with the anterior angle of the eyes, and 
is continued to a line above the origin of the pectorals, then a straight line 
is continued to the dorsal fin. The sides of the head project out from the 
body quite prominently over the eyes to the branchial aperture. Operculum 
directly in front of the pectorals, three inches in its greatest diameter. — Its 
motions are very sluggish, and it swims near the surface of the ocean. On 
account of the great elasticity of its flesh, it is captured with great diffi- 
culty ; it is generally gafted at or near the branchial aperture. Its flesh is 
sometimes used for balls. Its liver is very oily, furnishing two or more 
quarts of oil, which is used by the fishermen to grease their masts with, and it 
is also by many of them considered a valuable application in cases of sprains 
and bruises.” 
The Second Family of the Plectognathi (Scleroderm?) is composed of 
fishes with hard and granulated skins. They have a conical muzzle, which 
is prolonged forwards from the eyes, and terminates in the mouth, with dis- 
tinct teeth in both jaws. The skin is either rough or covered with very hard 
scales. Some of the species abound in the warm seas, near rocks, or on the 
