FAMILY POMACENTRIDAE — WOODS AND SCHULTZ 61 



light tan; back and sides dark blackish brown, posterior half of 

 caudal peduncle pale yellov/ish; spiny dorsal dusky, soft dorsal dusky 

 basally, pale on distal half; caudal pale yellowish, anal blackish; 

 pectorals pale whitish or yellowish ; pelvics black. 



Remarks. — This species is characterized by the single white bar on 

 the head; plain black body; pale soft dorsal, caudal, and pectoral; 

 but black pelvics and anal. 



Genus DASCYLLUS Cuvier 



Dascyllus Cuvier, Rfegne animal, ed. 2, vol. 2, p. 179, 1S29 (type species, Chaetodon 

 aruanus Linnaeus). 



KEY TO SPECIES OF DASCYLLUS FROM THE NORTHERN MARSHALL ISLANDS AND 



ADJOINING REGIONS 



la. Dorsal rays XII, 12, the second spine % the length of the third; head and 

 body with 3 broad transverse black bands, ifirst from origin of dorsal 

 fin through eye to chin, second from about middle of spinous dorsal 

 through base of pectorals to pelvics, third from anterior soft dorsal rays 

 to anal rays, spaces between bands whitish or brownish; caudal fin entirely 

 pale or shghtly dusky basally; anal raj^s 11,12 or 13; pectoral ii,15 or 16; 



gill rakers on first arch 23 or 24 D. amanus (Linnaeus) 



16. Dorsal rays XII, 14 to 16, the second spine subequal to third, pectoral rays 

 ii,18 or 19. 

 2a. Body with a narrow brown vertical bar extending from origin of dorsal 

 through pectoral base to base of pelvics (young specimens 14 to 16 mm. 

 with a second vertical dark band from soft dorsal to anterior part of 

 anal); general body color light yellowish, each scale with a narrow 

 brown submarginal line; dorsal rays XII, 14 to 16 (usually 15); anal 

 11,13 or 14; gill rakers on first arch 27 or 28. 



D. reticulatus (Richardson) 



26. Body without dark vertical bar but with a white spot on sides below 7th 



to 11th dorsal spines; sometimes with a small white nuchal spot (in 



young) . 



3a. White spot on sides small or rarely absent, only slightly larger than pupil 



(in specimens of all sizes), situated in or just above 11th to 13th 



lateral line scales; general body color brown; each scale with dark 



submarginal fine; dorsal rays XII,15; anal 11,14; gill rakers on first 



arch 23 to 25 D. trimaculatus (Ruppell) 



3&. White spot on sides larger than eye (in specimens of all sizes) ; extending 

 from base of dorsal to below lateral line, or in specimens under 25 

 mm. white spot usually a wedge-shaped bar narrowing ventrally; 

 indistinct but still evident in large specimens (75 to 85 mm.) ; general 

 body pattern reticulated in large specimens the scales with pale 

 centers and dark submarginal line, blackish in smallest specimens; 

 head usually very dark brown; dorsal rays XII, 16 (rarely 15); anal 

 11,15 or 16; gill rakers on first arch 25. (Not yet found in Marshall 

 Islands.) 3D. albisella Gill 



