CENTROPOMUS. dt 
middle of eye or beyond, its greatest width 3-32 the diameter of eye. Praorbital weakly serrated; pre- 
operculum acutely serrated, the serre enlarged at the angle; 1 or 2 feeble spines at angle of praopercular 
ridge. Opercular flap not reaching the vertical from origin of dorsal. 8 or 9 well-developed gill-rakers 
and a few rudiments on the lower part of anterior arch. 73-80 scales in a longitudinal series, 9 or 10 
between middle of second dorsal and lateral line. Dorsal VIII, 110: third or fourth spine longest, 
2 the length of head. Anal ITI 6; second and third spines subequal in length, $—} the length of the 
fish. Pectoral 4 or a little more than 4 the length of head. Ventrals not reaching vent, which is 
situated at about 2 of the distance from base of ventral spine to origin of anal. Caudal peduncle 13-2 
as long as deep. Silvery, back brownish ; lateral line blackish; spinous dorsal usually blackish ; other 
fins usually more or less dusky. 
Hab. Pacific Coasts of Tropical America, entering rivers: 
Mexico, Mazatlan45, Rio Presidio‘ (Forrer), Rio Mascota’ (Buller); Guate- 
mala, Chiapam ! 2 (Salvin); Panama®°®. 
Here described from three specimens, 150-300 mm. in total length, from the Rio 
Presidio, the Rio Mascota, and Chiapam. 
This species is very closely allied to C. viridis, but the anterior processes of the air- 
bladder are wanting, whilst the third dorsal spine is shorter, the scales are somewhat 
smaller, and the vent is placed a little further back. There appear to be constantly 
10 branched rays in the second dorsal fin. 
7. Centropomus robalito. 
Centropomus armatus (non Gill), Giinth. Trans. Zool. Soc. vi. 1868, p. 408°. 
Centropomus robalito, Jord. & Gilb. Proc. U.S. Nat. Mus. iv. 1882, p. 462°; Jord. & Everm. Bull. 
U.S. Nat. Mus. xlvii. 1896, p. 1123*; Gilb. & Starks, Mem. Calif. Ac. Sci. iv. 1904, p. 94, 
t. 18. fig. 25°. 
Centropomus ensiferus (part.), Bouleng. Cat. Fish. 1. p. 869 (1895) °. 
Depth of body 33-82 in the length, length of head 22-23. Snout 13-2 as long as eye, the diameter of which 
is 6-74 in the length of head; interorbital width 8 in the length of head. Maxillary extending to below 
middle of eye, or nearly, its greatest width 3-4 the diameter of eye. Praorbital acutely serrated 
posteriorly ; preoperculum acutely serrated, with 1 or 2 enlarged serre at the angle ; praopercular ridge 
with 1 or 2spines at the angle. Opercular flap extending a little beyond the vertical from origin of 
dorsal. 17-19 gill-rakers, including 2 or 3 rudiments, on the lower part of anterior arch. 48-54 scales 
in a longitudinal series, 5-64 between middle of second dorsal and lateral line. Dorsal VIII, 1 10; 
spines of moderate strength, the third the longest, about 3 the length of head. Anal Iii 6; third spine 
3-5 as long as second, which is from j to a little more than ; the length of the fish. Pectoral 2 as long 
as head. Ventrals extending about to the vent, which is situated at 2 of the distance from base of 
ventral spine to origin of anal, Caudal peduncle 14-13 as long as deep. Silvery or golden, back 
brownish ; lateral line not blackish; spinous dorsal and membrane between second and third anai spines 
usually blackish. 
Hab. Pacific Coasts of Tropical America, entering rivers: 
Mexico, Rio Presidio® (Forrer), Mazatlan 2°, Acapulco?*; Guatemala, Chia- 
pam 15 (Salvin); Panama ?*. 
Here described from nine specimens, 180-300 mm. in total length, from Panama, 
Chiapam, Mazatlan, and the Rio Presidio. 
H2 
