FISHES OF CHESAPEAKE BAY 
45 
3. Genus GINGLYMOSTOMA Muller and Henle. Nurse sharks 
Body moderately elongate, compressed posteriorly, depressed anteriorly; head broad; snout 
very blunt; nostrils near tip of snout, remote from each other, connected with the mouth by a groove, 
each anteriorly with a cylindrical barbel; mouth broad, little arched; teeth small, compressed, with 
a strong central cusp and one or more smaller lateral ones; several series functioning; spiracle 
minute and behind eye; gill slits moderate, the last two close together and above base of pectoral; 
dorsal fins rather close together, the first over the ventrals, the second somewhat in advance of 
anal. 
3. Ginglymostoma cirratum (Bonnaterre). Nurse shark. 
Squalus cirratus Bonnaterre, Tableau Encyclop., Method Nat. Ichthyol., 1788, p. 7; American seas. 
Ginglymostoma cirratum Lugger, 1877, p. 90. Jordan and Evermann, 1890-1900, p. 20, PI. IV, fig. 13; Garman, 1913, p. 54, 
pi. 7, figs. 4 to 6. 
Body posteriorly compressed, head and anterior part of body broad, depressed; snout short, 
broadly rounded; mouth much in advance of eyes, broad; teeth small, with sharp median cusp 
and a shorter one at each side; nostrils nearly at margin of snout and connected with mouth by a 
groove, each with a barbel; eye very small, the greatest diameter a little shorter than the longest 
gill slit in young, proportionately much shorter in adult; spiracle situated just behind eye, very 
small; denticles on skin below base of dorsal irregular in size, triangular, slightly imbricate, one or 
three keeled; origin of first dorsal over ventrals; second dorsal a little smaller; caudal long, angles 
rounded, lower lobe not produced; anal smaller than second dorsal, its origin under middle of second 
dorsal; pectoral fins nearly as broad as long. Color grayish or yellowish brown above, somewhat 
paler below. The upper parts either with or without round black spots. 
No specimens of this shark are at hand. The above description was compiled from published 
accounts. 
Gudger (1921, p. 58), after examining specimens of this shark taken in southern Florida, with 
reference to stomach contents, says : “Its food, in keeping with its tooth structure, is mainly confined 
to invertebrates, squid, shrimp, the so-called crawfish (Palinurus), short-spined sea-urchins, small 
fish, and probably the more thick-bodied, succulent algae. In short, the fish is more or less 
omnivorous.” 
The nurse shark, according to Gudger (1921, p. 59), is “ovoviviparous.” The eggs are large, 
about 75 millimeters in diameter when they break through the walls of the ovary, and brownish, 
horny shells with blunted ends, bearing tendrils (as in some of the egg-laying sharks and rays) are 
later provided. These egg cases measure from 120 to 140 millimeters in length and 170 to 190 
millimeters in circumference. The eggs then remain in the posterior part of the oviduct, where a 
“saddle-bag shaped” section is provided for them, until the young are hatched. 
Habitat . — Tropical Atlantic and eastern Pacific; apparently not recorded from the Atlantic 
coast of America north of Chesapeake Bay. 
Chesapeake localities. — (a) Previous records: “Southern part of Chesapeake Bay” (Lugger, 
1877). ( b ) Specimens in collection: None; not seen during the present investigation. 
Family IV. — LAMNID4i. The mackerel sharks; the man-eater sharks 
Body robust; head conical; tail slender, the peduncle depressed, with lateral folds and caudal 
pits; nostrils oblique, near the mouth but not confluent with it; eyes without nictitating membrane; 
mouth broad; teeth large; spiracles small or wanting; gill slits wide, all in front of pectorals; first 
dorsal large; second dorsal and anal small; caudal lunate; pectorals large, falcate. 
4. Genus CARCHARODON Muller and Henle. Man-eater sharks 
Body very robust anteriorly; head conical; caudal peduncle strong, depressed; teeth large, 
compressed, serrate, triangular, the upper teeth broadest; first dorsal large, nearly midway between 
pectorals and ventrals; second dorsal and anal very small; pectorals large. 
