I04 DireHors Annual Report. 



Genus HOI^ACANTHUS I^acepede. 



191. Holacanthus imperator (Block.). 



Head 4; depth 1.75; e3'e 3.36, about equal to width of inter- 

 orbital space; D. xiv 20; A. iii 19. Preopercle serrated and armed 

 with a spine which in adults is almost a third longer than width of 

 opercle. Teeth setiform in closely set rows. Fins: The dorsal 

 spines short, the longest about equal in length to the base of pec- 

 torals. Posterior of anal, dorsal and caudal rounded. All the fins 

 black, except the caudal which is yellowish. The vertical edge of 

 dorsal is also tipped with yellowish. The anal is edged with a 

 narrow line of blue, and a blue line runs out on the spine of the ven- 

 trals. Color dusky blue, with about 14 yellowish lines passing 

 obliquely upward to the dorsal, or horizontally to the caudal, or the 

 anal; the.se stripes are about one-fourth as wide as the interorbital 

 space, and the ones passing to the dorsal are most oblique. 

 A large black descending band, with a blue anterior edge, on the 

 shoulder. Another black band of almost equal width, and edged 

 all around with blue, occupies the interorbital space, passes over 

 eyes and comes to a sharp point on the preopercle just above the 

 spine. The opercle is yellowish brown with the above mentioned 

 blue lines bordering it fore and aft. Length about 6 inches. Speci- 

 mens were secured inside the coral reef near Agana, Guam, June 14, 

 1900. Hab. East coast of Africa, through seas of India to Malay 

 Archipelago, Marianas. 



192. Holacanthus marianas sp. nov. 



Head 3.50; depth 1.50; eye 2.75; maxillary 3.50; interorbital 

 3.20; D. XIV 20; A. Ill 19; V. I 5. Scales very small, feeling 

 velvety to the touch. Body elevated and compressed. Head with 

 moderately rounded profile, the snout but slightly projedling. 

 Teeth .setiform. Branchio.stegals 6. P.seudobranchiae well de- 

 veloped. Preopercle serrated, with a .spine on lower part equal in 

 length to the width of the opercle; this spine contained 3.50 times 

 into head. Fins: Dorsal spines of moderate strength, the longest 

 spine 2 into head. Po.sterior of dorsal and anal rounded. Caudal 

 1. 16 into head, its posterior margin rounded. Pe(5torals the same 

 length as head, the width of base 3. Ventrals with second ra}' pro- 

 duced into a .short filament. Color in spirits: Bluish black, with 

 about 13 more or less complete yellowish lines; the anterior of these 

 lines, beginning at the base of the eighth dorsal spine, curves for- 

 ward forming a margin of the jet black area of shoulders and then 

 curves back to the anal opening; the remaining yellow lines above 

 the axis are almost horizontal; the lines below the axis are verv 

 oblique, extending downward and back. Three of the lines on 

 the axis are incomplete, being shorter than the head. There is a 

 black area, the width of the eye, on the shoulders forming a line 



