FISHES OF THE GULF OF MAINE 



315 



THE SEA HORSES. FAMILY HIPPOCAMPIDAE 



Sea horse Hippocampus hudsonius DeKay 1842 

 Jordan and Evermann, 1896-1900, p. 777. 



Figure 173. — Sea-horse (//ippoca mp us Audsonius), Virginia. 

 From Goode. Drawing by H. L. Todd. 



Description. — The sea horse grotesquely re- 

 sembles the "knight" in an ordinary set of wooden 

 chessmen in its sidewise flattened body, in its 

 deep convex belly, in its curved neck and in its 

 curious horse-like head carried at right angles 

 to the general axis of the body. The head is 

 surmounted by a pentagonal star-shaped "coro- 

 net," and the snout is tubular with the small 

 oblique mouth at its tip, like that of its relative 

 the pipefish. It has a sharp spine on each side 

 above the eye and one behind it, a third over the 

 gill cover, and a fourth on the side of the throat, 

 which sometimes terminate in short fleshy fila- 

 ments; also a blunt horn between the nostrils. 

 Its neck, body, and tail are covered with rings of 

 bony plates, 12 rings on the trunk, 32 to 35 on 

 the tail, and each body ring is armed with four 



blunt spines. The body tapers suddenly behind 

 the anal fin to a long tail, which is four-cornered 

 in cross section, curled inward, and strongly pre- 

 hensile. In the male the lower surface of the fore 

 part of the tail bears the brood pouch, opening 

 by a slit in front. The dorsal fin (about 19 rays) 

 originates about midway of the length of the fish, 

 opposite the vent, and runs backward over three 

 and one-half rings to within half a ring of the 

 commencement of the tail sector of the trunk. 

 The very small anal fin stands opposite the rear 

 part of the dorsal fin. The pectorals are of 

 moderate size, broad based and round tipped; it 

 has no ventral fins and no caudal fin. 



Color. — Light brown or dusky to ashen gray or 

 yellow, variously mottled and blotched with paler 

 and darker, sometimes spangled with silver dots, 

 sometimes plain colored. European sea horses 

 change color according to their surroundings, tints 

 of red, yellow, brown, and white all being within 

 their capabilities, and it is probable that the Ameri- 

 can species is equally adaptable. 



Size. — Adults usually are 3 to 6 inches long; one 

 of 7% inches is the largest on record. 84 



Habits. — Sea horses dwell chiefly among eel- 

 grass and seaweed, 85 where they cling with their 

 prehensile tails, monkeylike, to some stalk. They 

 usually swim in a vertical position by undulations 

 of the dorsal fin, not with the tail, the trunk 

 being too stiff for much sidewise motion. 



Sea horses feed on minute Crustacea and on 

 various larvae, in fact on any animal small enough, 

 sucking in their prey as the pipefish does (p. 313.) 

 They breed in summer 86 and the breeding 

 habits resemble those of the pipefish, the male 

 nursing the eggs in his brood pouch where they 

 are deposited a few at a tune by the female in 

 repeated pairings. The young, of which there 

 may be as many as 150, are about 10 to 12 mm. 

 long at hatching. When the yolk sac is absorbed 

 the father squeezes them out of the brood sac, 

 and they already resemble the adult in general 

 appearance within a few days after they are set 

 free. According to some students they swim out 

 and in at will, but this calls for verification. 



" Bull. New York Zool. Soc, vol. 16, 1913, p. 972. 



»•" QUI (Proc. U. S. Nat. Mus., vol. 28, 1905, pp. 805-814) has given an ex- 

 cellent account of the habits and life history of the sea horse. 



»« Ryder. (Bull. U. S. Fish Comrn., vol. I, 1882, pp. 191-199) describes its 

 development. 



