HISTORY OF THE FISHES OF MASSACHUSETTS. 219 



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 of 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 stria; 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 



voi,. vm. 36 



