350 
BULLETIN OF THE BUREAU OF FISHERIES 
KEY TO THE GENERA 
a. Body with slender, sharply pointed, movable spines Diodon, p. 350 
aa. Body with shorter, less sharply pointed, immovable spines Chilomycterus, p. 350 
156. Genus DIODON Linnaeus. Porcupine fishes 
Body robust, inflatable; head short, broad; teeth in both jaws with a continuous cutting 
edge, no median suture; nasal tube simple, with two lateral openings; body everywhere with strong, 
pungent spines; dorsal and anal similar, posteriorly inserted; caudal fin round; ventral fins wanting; 
pectoral fins broad, the posterior margin truncate, the upper lobe longest. A single widely dis- 
tributed species was once recorded from Chesapeake Bay. 
198. Diodon hystrix Linnaeus. Porcupine fish. 
Diodon hystrix Linnseus, Syst. Nat., ed. X, 1758, p. 335; India. Uhler and Lugger, 1876, ed. I, p. 85; ed. II, p. 71; Jordan and 
Evermann, 1896-1900, p. 1745, PI. CCLXVI, fig. 648. 
7 Trichodiodon pilosus Uhler and Lugger, 1876, ed. I, p. 87, ed. II, p. 72. 
Head 2.2 to 2.4; depth 2.45 to 3; D. 13 or 14; A. 12 or 13. Body robust, rather broader than 
deep when not inflated; head depressed, notably broader than deep; snout very short, 2.8 to 3.1 in 
head; eye 2.85 to 3.45; interorbital very broad concave, 1.4 to 1.5; mouth rather broad; gill slit not 
longer than eye; skin thickly beset with strong sharp spines, longest on top of head, back, and sides; 
dorsal and anal fins similar, placed far back, the dorsal beginning somewhat in advance of the anal; 
caudal fin round; pectoral fins broad, the upper rays longest, 1.65 to 2.33 in head. 
Color dusky above, white below, entire body and fins marked by small round spots. 
This porcupine fish was not seen during the present investigation. It is included because of a 
record ’dating back to 1876 (Uhler and Lugger, 1876). The fish has not been seen in Chesapeake 
Bay by more recent investigators. The foregoing description is based upon published accounts of 
the species. The porcupine fish is readily recognized by the long, sharply pointed, movable spines, 
which cover nearly the entire body. 
Although this fish has been known to science for several centuries and from many parts of 
the world, we are unable to find information relative to its feeding and breeding habits. The 
species is said to reach a length of 3 feet. It is regarded as a curiosity by many and is rather 
extensively sought by travelers. Mounted specimens are common in nearly all museums. The 
species apparently has no value as food. 
Habitat . — All warm seas; northward on the American coast to Massachusetts; uncommon 
north of Florida. 
Chesapeake localities. — (a) Previous record: In Chesapeake Bay off the southern extremity of 
St. Mary’s County, Md. (Uhler and Lugger, 1876). (6) Specimens in collection: None; apparently 
very unusual in Chesapeake Bay. 
157. Genus CHILOMYCTERUS Bibron. Bur fishes 
Body broad, depressed, more or less inflatable; nasal tube simple, with two lateral openings; 
teeth in the jaws without median suture; dermal spines with three roots, immovable, triangular; 
caudal peduncle short. A single species is known from Chesapeake Bay. 
199. Chilomycterus schcepfi (Walbaum). Bur fish; Spiny toadfish; Thorny toad. 
Diodon schoepfi Walbaum, Artedi Pise., 1792, p. 601; Long Island, N. Y. 
Chilomycterus geomelricus Uhler and Lugger, 1876, ed. I, p. 86; ed. II, p. 72. 
Chilomycterus sp. Bean, 1891, p. 83. 
Chilomycterus schoepfi Jordan and Evermann, 1896-1900, p. 1748, PI. CCLXVI, fig. 649; Evermann and Hildebrand, 1910, 
p. 162. 
Head 2.1 to 2.75; depth about 3 or 4 (when not inflated); D. 11 or 12; A. 10. Body robust, 
somewhat broader than deep; head short, broad; snout very short and broad, 2.15 to 2.35 in head; 
eye 3.8 to 4.5; interorbital broad, concave, 1.45 to 1.75; mouth small, terminal; teeth in a con- 
tinuous plate in each jaw; scales wanting; skin everywhere, except on caudal peduncle, with 
more or less compressed three-rooted spines; two spines over orbit; one on middle of forehead; 
