FISHES OF HAWAIIAN ISLANDS. 
413 
Genus 185. BALISTAPTJS Tilesius. 
This genus has the head and body closely scaled, the scales of the posterior parts more or less 
spinous; enlarged scales behind the gill-opening, the lateral line obsolete and no groove before the 
eye. Species numerous in the Indian and tropical seas, small and rather brightly colored. 
Balistapus Tilesius, Mem. Ac. Nat. Sci. Petersb., VII, 1820, 302 ( capistratus of Tilesius, not of Shaw, undulatas). 
Jthinecanthus Swainson Classn. Anim., II, 325, 1839 ( ornatissimus=aculcatus ). 
a. A broad black band on side, extending downward and backward, from eye and lower base of pectoral, to vent and 
fourth from last anal ray; a wedge-shaped black band covering entire caudal peduncle, pointed anteriorly, and 
bounded by narrow, greenish lines rectangulus p. 413 
a a. No black band on side; no black wedge-shaped band on caudal peduncle; lor 5 oblique stripes on lower posterior side 
of body; a pale patch under caudal spines aculeatus, p. 414 
336. Balistapus rectangulus (Bloch & Schneider). “ Humuliumu nukunuku apua’a.” Plate LXIII. 
Head 2.6 in length; depth 2; snout 1.25 in head; eye 5.3; interorbital 3.75; I>. in, 26 (24 to 26); 
A. 20; first, dorsal spine 2.3 in head, equal to length of pectoral; longest dorsal ray 2.8; base of soft 
dorsal equal to shout; longest anal raj' 3, base of anal 1.65 in head; scales 40, 28 front anterior base 
of spinous dorsal to vent; interorbital space prominent, equal to cleft of mouth. 
Body oblong, compressed, dorsal and anal outlines similarly and evenly arched; head large; 
snout long, thick and blunt; mouth small, with thick lips; a single row of 8 sharp-notched, incisor- 
like teeth in each jaw; eye small, high, posterior; first dorsal commencing above the gill-opening, the 
first spine blunt and strong, its anterior edge rugose; soft dorsal and anal moderate, with rounded 
profile; caudal slightly rounded; ventral spine movable, supported by a series of slender sharp spines; 
pectorals broad, rounded; entire body and head scaled, some osseous plates behind the gill- 
opening; three and a half rows of sharp recurved spines on side of caudal peduncle. In a smaller 
example, 5 inches long, the upper row is the short row, in the larger examples, 8 inches long, the 
rows are irregular and sometimes as many as 6 are present; the number of rows does not seem to be 
uniform. 
Color in life, tipper part of body and head light brown, becoming lighter toward snout; 3 narrow 
black bands reaching from one eye to the other, the borders and spaces, wider than the bands, green; 
the posterior band on head passing downward, and after an abrupt bend backward just above gill- 
opening, becoming a violet line running along middle of body to a vertical from tip of third dorsal 
spine, where it forms an acute-angled fork, each prong a brilliant yellow line, the upper ending at 
about base of third from last dorsal ray, the lower ending at a corresponding position on base of anal; 
within the fork are 2 other bright yellow lines parallel with the prongs of the fork, forming anteriorly 
an acute angle on a vertical through the first third of dorsal. 
Color in life of another example (No. 03358, Honolulu), top of head, back, and upper half of side 
dusky light orange-brown, interocular region dusky greenish-blue, brighter blue on anterior and 
posterior edges, crossed by 3 narrow black lines, one ending at middle of orbit above and one each at 
anterior and posterior border; below eye a black area at first as broad as eye, then widening, inclosing 
pectoral and extending downward and backward to vent and as broad as to fourth from last anal ray, 
this bounded anteriorly by 2 pale blue bars separated by a narrow dull orange one; a similar blue 
border along upper margin to near middle of side, where it changes to a bright greenish-yellow band 
extending to base of last anal ray but 2; at point where this line changes from blue to yellow, a 
similar line leaves it and passes across side to third dorsal ray from the last; caudal peduncle jet black, 
extending forward in a sharp point and bounded in front and behind by narrow greenish-yellow lines; 
snout brownish-white, a rather broad pale blue band over snout and down to angle of mouth on each 
side; soft dorsal, anal, and caudal pale, the latter with a broad light brown bar on basal part; spinous 
dorsal dusky, brownish, or black; vent black; pectoral jet black at base, then a rich red crescent, 
outer part of fin blackish-white; iris dull brown; belly white. 
Color in alcohol, grayish brown abovh, becoming lighter below; a very dark blackish brown band 
passing through and downward from eye, widening below eye to lower base of pectoral, continuing 
backward to vent, its width on body being from vent to posterior third of anal; a small, narrow, 
similarly colored line extending from anterior part of eye to upper anterior base of pectoral, curving 
slightly forward; a light narrow violet band extending over snout from cleft to cleft of mouth; the 3 
