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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



Figure 245. — Common sea robin {Prionolus carolinus). Adult, New Jersey; from Goode, drawing by H. L. Todd. 

 A, egg; B, larva, just hatched, 2.8 mm.; C, young, 9 mm. A-C, after Kuntz and Radcliffe. 



Description. — The large head, tapering body, 

 and fanlike pectoral fins of the sea robin somewhat 

 suggest a sculpin. But the robin is distinguished 

 from all the sculpins by the incasement of its 

 entire head in bony plates; by its smaller mouth; 

 by the flat depressed dorsal profile of its snout; by 

 its large ventral fins; and by the fact that the 

 three lower rays of each of its pectoral fins are 

 separate from the rest of the fin and modified into 

 three independent feelers with slightly dilated 

 tips, a very noticeable and distinctive feature. 

 Furthermore, the front margin of the upper jaw 

 is concave in outline when viewed from above, 

 not convex as it is in most other fishes, which 

 gives the nose of the robin a characteristic aspect. 

 The head plates are rough and there is one sharp 

 spine on each cheek at the angle of the gill cover; 

 two short spines over each eye pointing backward ; 

 a spine on either side of the neck ; and one on each 

 shoulder above the base of the pectoral fin. The 

 spiny and soft-rayed portions of the dorsal fin are 



separate, but they are so close together at their 

 bases that they are almost in contact. The 

 spiny dorsal has 10 spines, is rounded in outline, 

 and higher than the soft dorsal (13 rays); but the 

 soft dorsal is considerably longer than the spiny 

 dorsal. 



The caudal fin is of moderate size, its margin 

 slightly concave. The anal fin (1 spine and 11 

 rays) is similar in outline to the soft dorsal, under 

 which it stands. The pectorals (their 3 lower rays 

 as just noted) are rounded in outline and are so 

 large that they overlap the anal and the second 

 (soft) dorsal when they are laid back. The ven- 

 tral fins (each of 1 stiff spine and 5 rays) stand 

 close behind the pectorals. 



Color. — Usually the body is grayish or reddish 

 brown above, with about five dark saddlelike 

 blotches along the back, and is dirty white or 

 pale yellow below. The dorsal fins are grayish, 

 marked with pale spots and stripes, with a black 

 spot between the fourth and fifth spines. The 



