HISTORY OF THE FISHES OF MASSACHUSETTS. 413 
extending its whole length. The inferior portion of the body posterior to the mem- 
branous flap is of a pinkish hue. The throat is of a bright yellow color. The 
pupils of the eyes are black; the irides are coppery. A yellowish-brown band 
passes downwards and backwards from the posterior angle of the eye to the centre 
of the operculum. Along the outer edge of the rostrum, from the eye almost to 
the snout, passes a dark-brown band. The dorsal fin is transparent, and indis- 
tinctly longitudinally banded with brown. ‘The pectorals and anal fin are colorless. 
The caudal fin is wholly brown. 
When the fish is preserved in spirits, the colors almost entirely disappear; the 
band on the outer edge of the abdominal flaps, the transverse bands on the back 
and sides, and the bands on the rostrum, are scarcely, if at all, perceptible; and 
the flesh-colored membrane of the pouches becomes of a dull white color. 
Description. Body elongated, compressed upon the sides, flattened above, and grad- 
ually tapering from the head to the tail; its whole surface being covered with horny, 
striated plates. The depth of the body just back of the pectorals, and also at the 
anus across, equal to one thirty-sixth its entire length; the width of the body at the 
anus is equal to half the depth back of the pectorals; the width at the centre of 
the pouches is equal to the depth back of the pectorals; the length vi the pouches 
is less than one third the length of the fish. 
The length of the head, from the extremity of the snout to the posterior angle 
of the operculum, is equal to one ninth the entire length of the fish. Rostrum 
tubular, compressed. The lower jaw is rather the longer, and passes obliquely up- 
wards to form the mouth. The eyes are prominent, and very movable in their 
orbits. The orbitar edges being elevated, a depression is seen between the eyes; 
in the centre of this depression arises a slight ridge, which is continued upon the 
top of the rostrum to the tip of the snout; upon the top of the head is situated 
another ridge which is continued on the neck posterior to the origin of the pec- 
torals. The opercula are pectinated; or of the form of a Pinna, broad posteriorly, 
rounded beneath and behind, and covered with strie radiating from their circum- 
ference. 
The anterior portion of the body is heptangular: on each side of this portion are 
three ridges, and one upon the abdomen. One of these ridges commences at the 
posterior superior angle of the operculum, and is continued in a straight line nearly 
to the termination of the dorsal fin; this ridge forms the lateral boundary of the 
dorsum. 
The second ridge arises beneath the pectorals at their base, and, passing along 
VOL. VIII. 54 
