FISHES OF CHESAPEAKE BAY 
185 
69. Genus HIPPOCAMPUS Rafinesque. Seahorses 
Body compressed, tapering abruptly into a long, quadrangular, prehensile tail; head placed 
nearly at a right angle to the body, shaped remarkably like that of a horse; top of head with a star- 
shaped coronet; egg pouch of males placed at base of tail, immediately posterior to vent; dorsal fin 
moderate, usually placed over vent; anal fin usually present, small; pectoral fins short and broad. 
91. Hippocampus hudsonius De Kay. Common American seahorse. 
Hippocampus hudsonius De Kay, Fauna of New York, Fishes, 1842, p. 322, PI. LIII, fig. 171; New Y ork. Uhler and Lugger, 
1876, ed. I, p. 90; ed. II, p. 75; Jordan and Evermann, 1896-1900, p. 777, PI. CXXI, fig. 327; E vermann and Hildebrand, 1910, p. 160. 
Head in trunk, measured over back from gill opening to end of dorsal base, 1.6 to 2.3; D. 18 
or 19; A. 4; body rings 12; caudal rings 33 to 36. Body with 7 angles; the tail with 4 angles; all 
angles provided with blunt spines; head also with spines; snout slender, 2.3 to 2.9 in head; eye 4 
to 6.2; mouth very oblique; dorsal fin over 3.5 or 4 body rings, its base 1.7 to 2.5 in head; pectoral 
fins about as broad as long, 3.25 to 4.5 in head. 
Color in preserved specimens uniform grayish brown or with dark lines and spots on sides, the 
lines most prominent on sides of head; dorsal fin spotted with black, the upper part of the anterior 
rays of the dorsal frequently black, forming a more or less definite black spot. 
Fig. 100. — Hippocampus hudsonius, adult 
This species is represented in the present collection by 11 specimens, varying in total length 
from about 40 to 150 millimeters. It is the only seahorse known from Chesapeake Bay. The 
southern allied species, H. punctalus, was once recorded from Ocean City and Somers Point, N. J., 
by Bean (1887, p. 134), which would indicate that stragglers may be expected, at least in the lower 
sections of the bay. H. pundatus does not have the dorsal placed wholly over body rings, the usual 
formula given for that species being 1^ or 2+1 or 2. The dorsal fin usually has somewhat fewer 
rays, although overlapping with H. hudsonius, the range being 16 to 18. Ii. pundatus is often 
profusely spotted with white or light blue, colors not occurring on H. hudsonius. 
The food of this fish, as in the pipefishes discussed in this report, appears to consist mainly of 
small crustaceans. The egg pouch of the male is situated immediately posterior to the vent and it is 
rather short and slitlike when closed, but round when the young are about to be extruded. (Smith, 
1907, p. 173. ) 15 
This seahorse is not very common in Chesapeake Bay, and it was taken only from Cedar 
Point southward, about half of the specimens at hand having been taken in the vicinity of Cape 
Charles. A few specimens were taken in March with the beam trawl by the Fish Hawk at a depth 
of 150 feet. Other specimens were seined during September, October, and November. The usual 
length is about 6 inches; rarely a length of 7 inches is attained. 
Habitat. — Massachusetts south to South Carolina, rarely straying northward to Nova Scotia. 
Chesapeake localities. — (a) Previous records: St. Marys River, Md., and Cape Charles city, 
Va. ( b ) Specimens in collection: From the vicinity of Cedar Point, Md., and vicinity of Tangier 
Island, Yorktown, Cape Charles, and Lvnnhaven Roads, Va. 
15 For an account of the early development of the seahorse see Ryder, 1882, pp. 191-199. 
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