486 PROCEEDINGS OF THE NATIONAL. MUSEUM vol.101 



Certain measurements were made, and these, expressed in thou- 

 sandths of the standard length, are recorded first for the holotype 

 and then for the paratypes, respectively. Standard lengths in mm. 

 114; 112 and 102. Greatest depth of body 632; 638 and 628; length 

 of head to rear of fleshy operculum 318; 295 and 304; postorbital 

 length of head 129; 130 and 130; length of snout 127; 112 and 108; 

 diameter of eye 97; 93 and 101; least depth of caudal peduncle 105; 

 103 and 98; length of pectoral fin 263; — and — (broken); length of 

 pelvics 272; 266 and 270; 'longest dorsal, thu"d or fourth spine, 285; 

 268 and 284; longest soft dorsal ray 158; 179 and 137; longest anal 

 spine, second, 290; 250 and 275; longest soft anal ray 255; 228 and 

 245; angles formed by dorsal and ventral profiles of head 80° to 95". 



Color in alcohol. — Ocular band present but indistinct, edges 

 brownish, central area pale, wedge-shaped above eye, oblong below 

 eye, with a central area of brownish sometimes a streak in form of a 

 small blotch; ocular band faintly visible on subopercle, but not 

 occurring on breast or under side of head; snout pale; upper lip a 

 little dusky; pelvics pale; caudal fin pale except a narrow blackish 

 posterior edge, broken off on holotype and one paratype; posterior- 

 dorsal part of body and dorsal fin with a broad black band extending 

 from base of second dorsal spine obliquely across body and posterior 

 part of anal fin a little behind tips of anal spines; margin of dorsal 

 fin white, with a narrow black submarginal streak from tip of fourth 

 dorsal spine to last dorsal soft ray, then below this on soft dorsal a 

 narrow white band somewhat broken; anal fin narrowly margined 

 with white; anterior ventral part of body pale or white, with center 

 of each scale marked with a small brownish spot; several of these 

 spots are especially intense brown behind and above axil of pectoral 

 fin. 



Color when alive. — Pale part of body probably was yellow, as some 

 of this color was present when specimens were received. 



Remarks. — Since the finding of an unnamed butterflyfish is a rare 

 occurrence, special care was taken to search the literature for species 

 close to the new one. None of the important contributions on the 

 Chaetodontidae or faunal studies that are listed in the accompanying 

 Literature Cited contain the present species from the Hawaiian 

 Islands, and it does not appear in any of the works on the fauna of 

 that area. 



Chaetodon tinkeri, with no vertical oblique or lengthwise dark 

 streaks on the sides, no transverse dark bars on caudal fins, and no 

 black pelvic fins, difi^ers from a vast group of species; among those 

 with black snouts it is closest to C. nigrirostris (Gill) (fig. 94) of the 

 eastern tropical Pacific, but tinkeri differs in having a pale snout 

 and in lacking black on the posterior border of the gill cover; the 

 chief resemblence is a broad black band dorsally. C. tinkeri resembles 



