FISHES OF HAWAIIAN ISLANDS. 
403 
spine; anal spines short, about 2 in first dorsal spine; anal rays short, 1.25 in first dorsal spine; caudal 
deeply lunate, the lobes pointed; ventral spine rough, sharp pointed, 2 in head; pectoral short, 1.4 in 
head. Skin uniform, rough velvety; caudal peduncle with 2 low, spiniferous plates on each side, dis- 
tance between them about two-thirds diameter of eye. 
Color in life of a specimen (No. 02980) 12.5 inches long, dirty olive, paler below; top of head and 
horn dark olivaceous; caudal spines pale blue; dorsal fin pale blue, crossed by about 6 narrow pale 
yellow lines, curving upward and backward, edge of fin narrowly blue; anal similarly marked, the 
blue border broader; caudal dirty olive, darkest in the center and on the upper and lower margins, 
posterior part pale olive; pectoral pale, brownish underneath; axil pale, with 2 or 3 small blue spots; 
ventrals pale. An example (No. 02997) 7 inches long, did not differ particularly from larger examples; 
general color pale olive, yellowish anteriorly; snout and top of head back to dorsal blackish; dorsal fin 
pale orange, crossed by narrow pale blue lines, the fin edged with blue; anal pale orange, with 2 broad 
pale blue bands, a narrower darker blue band at edge, with a narrow whitish border; caudal dusky; 
pectoral pale; ventrals whitish, darkish at tips; iris silvery, whitish yellow, a dark spot, above and 
another below. Another example (No. 03449), had the upper part of the body gray, the lower part 
yellow forward, with golden tinge along region of anal; dorsal fin dirty yellow, with verj^ narrow blue 
border; anal golden, with 2 narrow bands of bluish white parallel with outline of body, outer border 
same as dorsal, with narrow blue line; caudal grayish; ventrals yellowish; pectoral colorless. An 
example from Hilo when fresh was dirty olive, spines violet blue. 
Color in alcohol, dusky brownish above, paler below; caudal spines black; dorsal fin dark brown 
along base, the membranes above lighter brown crossed by pale bluish stripes extending upward and 
backward; anal similar to soft dorsal; ventrals pale, dusky at tip; pectoral dusky. 
This curious and interesting fish is abundant among the Hawaiian Islands, and is widely 
distributed in the tropical Pacific and the East Indies to the Red Sea. Jenkins obtained 9 examples 
at Honolulu, and we have 10 from the same place; also 3 specimens from Hilo. The Albatross found it 
at Honolulu and at Puako Bay, Hawaii. 
Our specimens are 4.5 to 14 inches long. 
Cluetodon unicornis Forskal, Descript. Animal., 63, 1775, Djidda. 
Monoeeros raii Schneider, Syst. Ichth., 181, 1801, no locality. 
Monoeeros biacnlcalus Schneider, Syst. Ichtli., 180, pi. mi, 1801, shores of Arabia. 
Naso fro nticornis Lacepede, Hist. Nat. Poiss., Ill, 105, 106, pi. VII, fig. 2, 1801, Isle of France. 
Acanthurus i unicornis , Shaw, Gen. Zool., IV, 374, pi. 50, 1803 (Indian and Arabian seas); .Jenkins. Bull. U. S. Fish. Coram., 
XXII, 1902 (Sept. 23, 1903), 481 (Honolulu); Snyder, op. cit. flan. 19, 1904), 534 (Honolulu; Puako Bay, Hawaii). 
Aspisurus unicornis, Rilppell, Atl. Reis. Nord. At, Fiseh., 60, 1828. 
Naseus tonrjicornis Cuvier in Guerm Meneville, Icon. reg. anim., pi. 35, fig. 3, 1830-44. 
Naseus fronticornis, Commerson in Cuvier & Valenciennes, Hist. Nat. Poiss., X, 259, 1885 ( Isle of France; Waigiou; Bourbon ; 
Tahiti; Carolines; Guam; Sandwich Islands; Red Sea at D.jedda; Cape Mohammed). 
Naseus olivaceus Cuvier & Valenciennes, Hist. Nat, Poiss., X, 2S8, 1835, Tahiti (young). 
Chsetodon olivaceus, Solander in Cuvier & Valenciennes, Hist. Nat. Poiss., X, 288, 1835. 
Harpurus monoeeros Forster, Descript. Animal., Ed. Lichtenstein, 219, 1844, Tahiti. 
Acvmiurus zegyptuis Gronoiv, Syst. Nat., Ed. Gray, 191, 1854, Red Sea. 
Acronurus cornirjer Gronow, Syst. Nat., Ed. Gray, 192, 1854, Red Sea. 
Naseus unicornis, Gunther, Cat., Ill, 348, 1861 (Ceylon; Frankland Island; Red Sea, Aneityum), Gunther, Fisehe der Sudsee, 
IV, 118, taf. lxxviii, figs. 1 to 4, 1875 (Tahiti; Lat. 13° S., Long. 146° W., north of Society Islands (Red Sea to Sand- 
wich Islands) ; Streets, Bull. U. S. Nat. Mus., No. 7, 68, 1877 (Honolulu); Steindachner, Denks. Ak. Wiss. Wien, LXX, 
495, 1900 (Honolulu; Laysan). 
Monoeeros unicornis, Fowler, Proc. Ac. Nat. Sci. Phila. 1900, 513, (Sandwich Islands). 
Genus 183. CALLICANTHUS Swainson. 
This genus differs from Acanthurus in having no horn upon forehead. Tail with 2 bony plates, 
with or without spines; dorsal spines 5 or 6; teeth not serrulate. Not very distinct from Acanthurus. 
Callieanthus Swainson, Nat. Hist. Fishes, etc., II, 256, 1S39 ( elegans ). 
a. Caudal spines scarlet interorbital comparatively narrow, about 3.4 In head; head with an orange or yellow line from 
eye to angle of mouth lituratus, p. 404 
aa. Caudal spines gray; interorbital wider, 3 in head; head without orange or yellow line metoposophron. p. 405 
