DESCRIPTIONS OF FISHES FROM THE HAWAIIAN ISLANDS. 
395 
This species is closely related to Chsetodon miliaris Quoy & Gaimard, 1 of tire East Indies, differing 
from it in having the spots in rows on every third vertical series of scales instead of on each scale. 
( Mantellum , mantle, in reference to arrangement of spots on the body. ) 
Numerous specimens collected by me at Honolulu, two secured by Dr. Wood. Type No. 49699, 
U. S. N. M. 
The following are the comparative measurements and the numbers of the fin rays and scales of 
three specimens: 
Chsetodon mantelliger. 
No. 1. 
No. 2. 
No. 3. 
Chsetodon mantelliger. 
No. 1. 
No. 2. 
No. 3. 
Length in millimeters . . 
82 
80 
65 
Snout 
.08 
.10 
.10 
.30 
.30 
. 30 
XU 1 
XIII 
99 
XII 1 
.65 
.60 
Second dorsal rays 
22 
. 26 
.27 
19 
18 
20 
Ventral 
.24 
.27 
.25 
Scales (longitudinal) ... 
57 
53 
51 
Eve 
.10 
.10 
.10 
Scales (transverse) 
9-22 
8-18 
9-24 
Interorbital 
.09 
.09 
.09 
Tubes on lateral line 
36 
42 
38 
Chsetodon sphenospilus Jenkins, new species. Fig. 8. 
Head 3.33 in length; depth 1.33 in length. D. xiii, 23; A. in, 19. Profile of head from snout 
to first dorsal very steep, first dorsal spine being situated over posterior edge of opercle. Snout very 
slightly obtuse. Profile of head slightly reentrant before eye. Profile of body from the nape almost regu- 
larly ovate to caudal peduncle. Eye elliptical, longer diameter longitudinal, 3 in head. Interorbital 
very slightly wider than length of eye, equal to snout. Preorbital four-fifths of vertical diameter of 
eye. Posterior edge of preopercle vertical, angle regularly rounded and minutely serrated. Posterior 
border of opercle slightly notched, without spines. Deep pit below lower end of premaxilla and 
another just back of lower end of maxilla. Dorsal spines back of second'd approximately uniform 
length, third 1.5 in head, second a little shorter than third, first less than half. of second; posterior 
spines successively slenderer. First soft rays equal to last spine, median rays longest, last very short, 
about one-third of median rays, so that border of fin is rounded and posterior margin receding. Soft 
anal of same size and shape as soft dorsal. Second and third anal spines of equal length, equal to 
third dorsal spine; first one-half of second. Posterior edge of caudal fin about straight, a little oblique, 
upper rays being longest. Pectoral equal to head, upper rays longest. Ventral equal to pectoral, 
outer rays longest. All parts of head and body scaled except maxillaries and symphysis of lower jaw. 
Scales on head and fins very small, those on body mostly larger, those of anterior half of body back of 
bases of pectorals and ventrals much larger. Scales on body 7-56-21. Lateral line not concurrent 
with dorsal profile, begins back of upper part of eye, curves upward to black spot on upper part of 
side of body, then downward to base of last dorsal ray, where it terminates. 
Color in life: Fins and upper part of body yellow, especially bright on ventral and anal fins; 
ocular band black, passing vertically through eye, width on side of head equal to eye, on top of head 
covers space from above front of eye to first dorsal spine; face in front of ocular band white; tip of snout 
dusky; lower part of body, below end of pectoral fin, white; large black spot on upper part of side 
of body below the eighth to the tenth spines, extending vertically from the third scale below the 
dorsal fin to about the tenth scale from the anal spines; upper part of spot forming large round black 
blotch, lower part, below eleventh scale from dorsal, abruptly tapering and much paler than the 
upper part, so as to form a long slender downward wedge-shaped prolongation, comparatively faintly 
colored from an upper very black round spot; in front of lower part of lateral spot, above pectoral fin, 
seven light-yellow oblique bands (inclined from below upward and backward); a black band around 
middle of caudal peduncle bordered before and behind by a white band; soft dorsal and anal fins with 
a submarginal black band, widest posteriorly on horizontal rays of each, tapering to a narrow line on 
median and anterior rays, within this a white band, and beyond it a very narrow marginal line of white. 
This species is very closely related to Chsetodon unimaculatus Bloch, 2 differing from it mainly in the 
1 Chsetodon miliaris Quoy & Gaimard, Zoologie du Voyage de Freycinet, p. 380, pi. 62, fig. 5; Cuvier & Valenciennes, 
Hist. Nat. Poiss., vn, p. 26; Gunther, Cat. Fishes Brit. Mus., ii, p. 31; Gunther, Fische der Siidsee, p. 40, pi. 35, fig. A. 
2 Chsetodon unimacidatus Bloch, pi. 201, fig. 1; Bloch & Schneider, p. 221; Cuvier & Valenciennes, Hist. Nat. Poiss., vn, 
p. 72; Gunther, Cat. Fishes Brit. Mus., ii, p. 11. 
Tetragonopterus unimaculatus Bleeker, Atlas Ichthy., ix, p. 45, pi. 375 (Chset., pi. 13), fig. 5. 
