FISHES OF CHESAPEAKE BAY 
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The hammerhead is viviparous, as many as 37 embryos having been taken from an 11-foot 
fish. Along the Atlantic coast fish 2 to 6 feet long are not uncommon, while larger examples are 
reported occasionally. The largest hammerhead of which we find record was 17 feet long, har- 
pooned off Miami, Fla., on March 21, 1919. 
Habitat — -Tropical and temperate seas; on both coasts of America from Cape Cod, Mass., 
and California southward. 
Chesapeake localities. — (a) Previous record: Miles River, Md. ( b ) Specimens observed on 
present investigation: Lynnhaven Roads, Va., July, 1916, and June, 1921. 
9. Sphyrna tiburo (Linnaeus). Shovel-nose shark; Bonnet-nose shark. 
Squalus tiburo Linnaeus, Syst. Nat., ed. X, 1758, 231; America. 
Sphyrna tiburo Jordan and Evermann, 1896-1900, p. 44, PI. V, flg. 19. 
Body moderately slender, compressed; head much depressed, expanded, the anterior margin 
semicircular, the posterior margins short, free, slightly concave, its greatest width quite equal to 
its length to first gill opening; eye small, lateral, 4 in preoral length of snout, nictitating membrane 
present; mouth moderate, its width 1.05 in preoral part of snout; teeth in jaws similar, with broad 
basal shoulders and a sharp, smooth cusp, the lateral teeth with a notch behind the cusp, upper 
jaw with about 30 teeth in a series, the lower with about 27; longest gill slit 2.1 in preoral part of snout; 
dermal denticles slightly imbricate, 3 and 5 keeled, the median keels projecting as sharp lobes; 
first dorsal rather short and high, elevated anteriorly, its origin slightly behind base of pectorals, 
the base 2.96 in distance between dorsals; second dorsal small, its posterior lobe elongate, pointed, 
the base 5.5 in distance between dorsals; upper lobe of caudal long, pointed, 35 in total length; 
anal fin notably longer than second dorsal and beginning farther forward, its base 1.05 in distance 
from anal to base of lower lobe of caudal; ventral fins moderate, inserted about equidistant from the 
origin of the first and second dorsals; pectoral fins rather small, 7.1 in total length. 
Color grayish above, pale below. 
This shark is represented in our collection by one small male specimen, 662 millimeters (26 
inches) in length. 
The food, as determined from specimens taken at Beaufort, N. C., consists of fish, crabs, 
shrimp, and other crustaceans. 
This shark is viviparous, and as many as eight or nine young have been found at one time. 
(Smith, 1907, p. 35; Radcliffe, 1916, p. 266.) 
This fish is comparatively rare in Chesapeake Bay, where only one specimen was observed. 
In the lower bay, between Ocean View and Cape Henry, however, fishermen said that it was occa- 
sionally taken in pound nets and they knew it well enough to give it the name “shovel-nose shark.” 
The maximum length attained is given as about 5 feet. 
Habitat . — Tropical and temperate seas (Garman, 1913, p. 161); northward on the Atlantic coast 
of America to Long Island. 
Chesapeake localities. — (a) Previous records: None. (6) Specimen in collection: Lynnhaven 
Roads, Va., pound net, June 9, 1921. 
Order TECTOSPONDYLI 
Family VII. -SQUALID/E. The dogfishes 
Body elongate; head depressed; eyes lateral, no nictitating membrane; nostrils inferior, separate, 
remote from the mouth; mouth rather large, inferior, with labial folds and a deep groove at each 
angle; spiracles present; gill slits 5, all in front of pectoral; dorsal fins 2, each preceded by a spine; 
no anal fin. 
9. Genus SQUALUS Linnaeus 
Body rather slender; head flattened below; snout produced, tapering; nostrils transverse, 
inferior, remote from mouth; spiracles behind eyes; mouth wide, little arched, with a deep groove 
and with labial folds at each angle; teeth compressed, alike in both jaws, with oblique cusps; dorsal 
spines not grooved on sides; first dorsal near the pectorals; second dorsal behind ventrals; caudal 
pits present; lower lobe of caudal produced. 
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