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BULLETIN OF THE UNITED STATES FISH COMMISSION. 
blue spots, fainter ones scattered over body; a group of linger-like bars upward from base of anal, and 
another behind the first on caudal peduncle; fins pale, except the caudal, which has some orange on 
middle rays, upper and lower rays brown, their bases each with a black blotch. In spirits, much the. 
same, the blue becoming brown. 
A small and prettily colored puffer, not uncommon; found in the West Indies, north, in rather 
deep water, to the banks off Pensacola; also in the Madeira* and Bermudas. Seven examples, 1.75 to 
2.75 inches long, taken in the seine at San Antonio Bridge and Fajardo, and 2 from San Geronimo. 
Tdrodon rostraius Bloch, Ichthyol., I, pi. 146, 1782, India. 
Tetrodon capistratus Lowe, Proe. Zool. Soc. London 1839, 90, Madeira. 
Telrodon ornalus Poey, Synopsis, 433, 1868, Havana. 
Canthigaster rostratus, Jordan & Evcrmann, 1. c., 1741, 1898. 
Family LXI. DI0D0NTID7E. The Porcupine-fishes. 
Body short, broad, depressed above. Belly moderately inflatable, covered everywhere except 
on lips and caudal peduncle with spines, which are usually 2-rooted or 3-rooted at their bony base. 
Caudal peduncle short and slender. Mouth moderate, terminal, each jaw covered with a bony plate 
like the beak of a bird, these not divided by a median suture. Nostrils on each side forming a small 
tentacle, usually with two openings. Eye rather large, gill-opening moderate, immediately in front 
of pectoral, which is short, broad, and rounded. Dorsal and anal fins short, similar to each other, 
rounded in form and placed posteriorly. 
The Diodontidm comprise about 6. genera and 15 species, sluggish fishes, living on the bottom 
among weeds and corals, in tropical seas. When disturbed, they swallow air and float belly upward 
on the water. Their capacity of inflation is very much less than that of the Tetraodontidise, from which 
family they differ chiefly in the stronger armature and in having no division in the bony plate of 
either jaw. Barely used as food, being generally regarded as poisonous. The species are mostly well 
known in collections, the singular form having attracted the attention of travelers in the earliest times. 
a. Dermal ossifications very small, each one 2-rooted, with fine flexible spine or hair-like bristle. Nasal tentacles 
present Trichodiodon 
aa. Dermal ossifications mostly 2-rooted; spines rather slender, but stiff and erectile. Nasal tentacle simple, with 2 
lateral openings Diodon, 126 
aaa. Dermal ossifications all or nearly all 3-rooted, each with a short, stiff, immovable spine. Nasal tentacle simple, 
with 2 openings Chilomycterus, 127 
aaaa. Dermal ossifications of flattish, papery, or cartilaginous plates with minute hair-like papillae; nostril short, entire, 
with 2 lateral openings Lyosph.br a 
Genus 126. DIODON Linnaeus. Porcupine-fishes. 
Body robust, belly moderately inflatable. Dermal spines strong, stiff, most of them 2-rooted and 
erectile, a few 3-rooted and therefore immovable; both jaws entire; nasal tube simple, with two lateral 
openings. Pectorals broad, their margin undulate, upper lobe longest; vertical fins rounded, dorsal 
and anal short, posteriorly inserted, similar to each other. 
Found in tropical seas, the few species being very widely distributed. 
a. Spines terete. 
b. Frontal spines not as long as post-pectoral spines (in adults not half as long, about as long as eye); predorsal spines 
very short, 3-rooted, fixed or nearly so; 20 spines in a series between snout and dorsal; post-pectoral spines very 
much elongate, especially in adult, shorter in young; dorsal rays 15; anal 15; upper lobe of pectoral little 
longer than lower. Adult above everywhere covered with round black spots, these largest in front of dorsal, 
smallest on naked area about mouth; white below; fins profusely spotted with black; young with fewer spots, 
but never with large blotches hystrix , 228 
bb. Frontal spines long, usually longer than post-pectoral spines, about twice as long as eye in adult; predorsal spines 
not shortened, 2-rooted, erectile; 14 to 17 spines in a series between snout and dorsal; post-pectoral spines not 
especially elongate, their development variable; dorsal rays usually 12; anal 12; pectoral broader than long, 
its upper lobe pointed, lower lobe rounded. Body marked with black spots and blotches, irregular in size, 
usually a broad black bar from eye to eye, continued below eye as a narrow bar; a broad bar across occiput; a 
black blotch above each pectoral; a short bar in front of dorsal; another in which dorsal is inserted; a blotch 
behind pectoral, and many small spots and blotches on upper parts; fins with few spots, usually unmarked in 
the young ; holacanthua, 229 
an, "Spines compressed laterally, short; 15 spines in a series between snout and dorsal; upper parts covered with 
round spots, those about pectoral sometimes confluent into a blotch; fins immaculate” maculije >• 
