FISHES OF HAWAIIAN ISLANDS. 
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dorsal, the free edge concave; first dorsal bluntly pointed; second dorsal and anal equal in size, edge 
of anal deeply notched; edge of upper caudal lobe notched, distance from notch to tip of lobe 
4.54 in length of lobe. 
Color bluish gray above, the fins growing darker toward the tips; ventral surface lighter. 
The following are the measurements of a male taken at station 3902, off the northern coast of 
Molokai: Total length 224 cm.; tip of snout to dorsal 71; to eye 17.8; to gill-opening 44; to pectoral 
54; length of gill-area 13.5; height of first gill-slit 6.5; of second 7; of third and fourth 6.5; of fifth 
5.8; anterior margin of pectoral 49; base of pectoral 14; posterior margin of pectoral 42; axil of pec- 
toral to ventral 49.5; anterior margin of ventral 12.8; free margin of ventral 12.8; base of ventrals 10.8; 
axil of ventral to front of anal 19; base of anal 8.3; anterior margin of anal 12; anal to caudal pit 13.4; 
base of first dorsal 19.7; anterior margin of first' dorsal 30.5; free edge of dorsal 26; distance between 
dorsals 58; base of second dorsal 7; second dorsal to caudal pit 19; upper lobe of caudal 61; spread 
of caudal 66; lower caudal lobe 29; width of mouth 20.5; preoral length of snout 15. 
Type, No. 50860, IT. S. Nat. Mus., a female about 4.86 feet long, taken at French Frigate Shoals. 
A smaller example, also a female, from Laysan Island, does not differ from the type, except that it is 
darker in color, the under parts being quite dusky. Cotype, No. 12790, L. S. Jr. Univ. Mus., a 
female 32 inches long (No. 03741), and the heads of 2 larger examples were obtained at Honolulu. 
A large and voracious shark seen everywhere about the islands. Compared with Carcharias 
japonicus of Japan, it is more robust in form, having a shorter and broader head. 
Carchwias (Prionodon) gangeticus, Steindachner, Denks. Ak. Wiss. Wien, LXX, 1900, 519 and 521 (Laysan Island.) 
Carcharias nesiotcs Snyder, Bull. U. S. Fish Comm. 1902 (Jan. 19, 1904), 514, pi. 1, fig. 2, French Frigate Shoals. 
Family IV. SPHYRNID7E. 
General characteristics of the Carchariidse, but the head singularly formed, kidney-shaped or 
“hammer ’’-shaped, from the extension of its sides, the nostrils being anterior and the eyes on the 
sides of the “hammer”; mouth crescent-shaped under the “hammer”; teeth of both jaws similar, 
oblique, each with a notch on the outside near the base; no spiracles; last gill-opening over the 
pectoral, first dorsal and pectorals large, the dorsal nearer pectorals than ventrals; second dorsal and 
anal small; a pit at the root of the caudal; caudal fin with a single notch toward its tip, its lower lobe 
developed. One genus with 5 species, inhabiting most warm seas. Large sharks, known at once by 
the singular form of the head, which is not quite the same in any two species. 
Genus 7. SPHYRNA Rafinesque- 
Characters of the genus included above. In the form of the head there is a perfect gradation among 
the species from the narrow hammer of S. blochii, with the lobes three times as long as broad and 
deeply grooved along the anterior edge, to the kidney-shaped head of S. tiburo, in which the anterior 
grooves are obsolete. 
Sphyrna Rafinesque, Indice d’Ittiol. Siciliana, 60, 1810 (zygxna). 
Cestrorhinus Blainville. Journ. Phys. 1816, 264 (zygxna). 
Zygxna Cuvier, Regne Animal, Ed. I, 127, 1817 (zygxna)', name preoccupied. 
Platysqualus Swainson Classn. Anim., II, 318, 1839 (“tiburo” =tudes). 
Reniceps Gill, Ann. Lyc. Nat. Hist. N. Y., VIII, 1861, 412 (tiburo). 
Cestracion (Klein; pre-Linnsean) Gill, 1. c., 403 (zygxna). 
Eusphyrna Gill, 1. c., 412 (blochii). 
9. Sphyrna zygsena (Linnaeus). Hammer-headed Shark; “Mano kihikihi.” 
Head truly hammer-shaped; width of head about twice its length; length of hinder margin of 
hammer nearly equal to its width near the eve; nostril close to eye, prolonged into a groove which 
runs along nearly the whole front margin of head; first dorsal large; second quite small, smaller than 
anal ; pectoral rather large. Color gray. A large voracious shark reaching a length of 15 feet or more, 
found in all warm seas; occasionally on our coasts from Cape Cod and Point Concepcion, southward. 
A number of examples of this species were obtained at Honolulu, and it was taken by the Albatross 
at Station 3844, off the southern coast of Molokai. Dr. Jenkins also brought 13 examples from 
Honolulu in 1889, the largest measuring 20.5 inches. The species is also common in the South Seas 
and in Japan. 
