1558 BuUcthi 77, United States National Museum. 



young has been named JJavilatus. The coloration of the young is thus 

 described by Dr. Gill: 



"This species, so far as known, undergoes little change during its prog- 

 ress to adult age. The color above the lateral line, and on the scaly por- 

 tion of the dorsal fin before the middle of its soft part, is dark brown, 

 with blue on the center of each scale, while a large ocellus, very dark 

 blue, margined with light, adorns the back and the dorsal fin between the 

 last spine and the sixth ray ; and a small ocellus is on the back of the tail 

 behind the dorsal fin. Below the lateral line and behind the dorsal ocellus, 

 the color is brownish-yellow, darker in front along the margins of the 

 scales, and with an indistinct bluish dot in th(^ center of each scale, except 

 on the caudal peduncle, where they are absent. The head above has 2 

 blue lines^ 1 on each side, continued from the snout backward on the 

 nape; another line is continued from the upper angle of the orbit to the 

 row of scales above the lateral line. A bar crossf:s the preorbital and a 

 line interrupted passes along the suborbital chain ; a bar is behind the 

 ends of the maxillary. The scales on the cheeks and opercula are dotted 

 with blue. The dorsal fin, behind its produced rays, as well as the anal, 

 caudal, pectoral, and veutral fins are yellowish; the former faintly 

 marked with blue on its scales, and margined in front with dusky; the 

 ventrals are likewise margined on their outer edges with dusky." 



A specimen from a rock pool at Mazatlan was cohued as follows : An 

 irregular line from snout below eye to soft dorsal divides the fish into 2 

 parts; below this line all is brilliant yellow with an orange shade, deepest 

 on anal; above, all is the Inightest sky-blue; scales darker, but all edged 

 with sky-blue, 6 sky-blue stripes on upper part of head; an indigo spot 

 on base of first ray of soft dorsal and last dorsal spines, extending on back, 

 this surrounded by a ring of sky-blue; a similar smaller ocellated spot on 

 back of caudal peduncle. Length f inch. 



Cape San Lucas to Mazatlan and beyond; very abundant in rock pools; 

 the most brilliantly colored small fish in Mexican waters. Except for the 

 marked dift'ereuce in color, the species can scarcely be separated from 

 E. rectifraniim, an eciually abundant inhabitant of the same ^vaters. We 

 find, however, no intermediate forms, the 2 species seeming to be per- 

 fectly separated. It may be noted that a third inhabitant of the same 

 rock pools, Mivrospathodon bairdii, lias almost exactly the coloration of 

 Eupomaccntrus flavilatus. (Jiarus, yellow; laius, side.) 



Fomacentriis Jiavilatus, Gill, Proc. Ac. Nat. Sci. Phila. 1862, 148, Cape San Lucas (Coll. 

 Xautus) ; (Gill) Gunther, Cat., iv, 27, 1862; Gill, Proc. Ac. Nat. Sci. Phila. 1863, 215; 

 Jordan & Gilbert, Proc. U. S. Nat. Mus. 1882, 365. 



1»70, EUPOMACENTRUS PARTITUS (Poey). 



Height 3^ in total length with caudal {;ibout 2 J without). Color dark 

 brown, with posterior haif of the trunk yellowish, as also the border of the 

 tips of the soft dorsal and anal; caudal yellowish, blue posteriorly; pec- 

 toral orange, less so at base; rays of the fins dusky; whole soft dorsal 

 sometimes yellowish. Length 3 inches, t'uba. (Poey.) A doubtful spe- 

 cies not seen by us. {partitus, divided.) 

 Pomacentrus jiartitus, Poey, Synopsis, ;!27,1867, Havana. 



