A Collection of Fishes fro fu Samoa. 121 



Dascyllus aruanus (Linnaeus). 

 Three small examples from cove just south of Aua village. 



Chromis cseruleus (Cuvier). 

 Two adults from Pago Pago, 



Chromis isomelas Jordan and Seale. 



Head 3.16; depth 1.87; D. XII, 13; A. II, 14; P. I, 15; V. I, 5; tubes 14 in upper 

 arch of lateral line and 7 porous scales in horizontal section before caudal base; 3 scales 

 above lateral line to origin of spinous dorsal; 9 scales below lateral line in vertical row 

 to origin of spinous anal; 19 predorsal scales; width of head 1.5 its length; head depth 

 at occiput 1; snout 4; eye 2.75; maxillary 3.2; interorbital 2.4; fourth dorsal spine 2.12; 

 ninth dorsal ray about 1.75; second anal spine 1.9; ninth anal ray 1.4; least depth of 

 caudal peduncle 2. 



Body strongly compressed, deeply ellipsoid, deeper midway in combined head 

 and trunk. Edges all convex. Caudal peduncle well compressed, long as deep. 



Head deep, profiles about evenly inclined, with upper very slightly concave over eye, 

 compressed and flattened sides slope evenly above and below. Snout surface convex, 

 also profile, length half its width. Eye, also pupil, slightly ellipsoid, little advanced or 

 with posterior edge about midway in head length. Mouth small, oblique, terminal. 

 Lips narrow, rather thin. Teeth conic, in rather broad bands in jaws, outer row slightly 

 enlarged, also extend all along premaxillary edge. Mandible even with upper jaw 

 tip when closed, rather shallow and rami well elevated behind inside mouth. Buccal 

 membranes (breathing valves) present inside mouth, upper broader. Tongue pointed, 

 free, smooth, rather elongate. Nostril small, simple pore, about midway on side of 

 snout. Interorbital evenly convex. Preorbital narrow, about two-fifths of eye. 

 Suborbital and preopercle edges entire. 



Gill-opening forward to anterior edge of eye. Rakers 7-f 20, lanceolate, but little 

 shorter than filaments and latter slightly less than half of eye. Pseudobranchiae 

 large as gill-filaments. Isthmus narrowly constricted in front. 



Scales large, minutely ctenoid, rather narrowly imbricated, smaller along edges 

 of body. Cheek with 4 rows of scales. Single row of scales on preorbital and infra- 

 orbital. Small scales crowded densely over bases of vertical fins, though on spinous 

 portions forming a sheath basally, row of scales up behind each spine on membrane. 

 Small scales at pectoral base. Ventral with pointed axillary scale about one-third 

 of fin-length, median flap between fins about three-fourths length of axillary flap. 

 Scales with basal radiating stria? 7 to 10, sometimes 2 or 3 auxiUaries; small apical 

 denticles 98 to 110; circuli fine. Upper arch of lateral line extends back opposite 

 eleventh dorsal spine base. Tubes large, simple, each well exposed or over first 

 three-fifths of scale; also continued irregularly as 4 pores, then drops a scale and 2 

 more pores below soft dorsal. Horizontal section of lateral line of simple pores, begins 

 below soft dorsal opposite third pore of upper section, skips 1 or 2 scales, then continues 

 to caudal base. 



Spinous dorsal inserted immediately after pectoral base or much nearer snout tip 

 than origin of soft dorsal, spines graduated up to third and fourth, the longest, others 

 posteriorly but sHghtly shorter, edge of fin notched and little cutaneous flap behind 

 each spine tip. Soft dorsal inserted about last third in space between origin of spinous 

 dorsal and base of caudal, fin pointed, median rays longest. Spinous anal inserted 

 opposite ninth dorsal spine base or little nearer pectoral origin than caudal base, 

 second spine longer, first two-fifths its length. Soft anal like soft dorsal, only larger. 

 Caudal deeply forked and outermost rays of each lobe produced in long slender points, 

 length 1.87 in combined head and trunk. Pectoral reaches anal, upper rays longest, 

 and fin about 3 in combined head and trunk. Ventral inserted slightly behind origin 

 of pectoral, first ray ends in filament reaching soft anal origin. Ventral spine three- 

 fifths of fin. Vent directly in front of anal. 



