1118 Bulletin 47, United States National Museum. 



hkh. Scales largo, 49 to 53 in lateral line; eye moderate, about 6 in head; anal rays III, 6. 



J. Second anal spine moderate, about % depth of body, little longer than third; 



preopercle with 2 strong teeth; back steeply elevated. unionensis, 1524. 



a. Second anal spine extremely long, its length little, if any, less than depth of 



body; much longer than third anal spine. 



j. Body moderately elongate, the depth 334 *" '^% '" length. 



k. Scales before the dorsal small, 16 to 18 in number; maxillary reaching 

 past front of pupil. Third dorsal spine half head; scales 51. 



ARMATUS, 1525. 

 kk. Scales before dorsal not crowded, 10 to 14 in number; maxillary barely 

 reaching front of pupil; third dorsal spine not (juite half head; 

 scales 51. 

 /. Third dorsal spine less than half head; scales 47 to 50. 



ROBALITO, 1526; AFFINIS, 1527. 



Jj. Body more elongate, the depth 4 in length; second anal spine excessively 

 long, Ig times depth of body; scales 53. ensifeuus, 1528. 



1515. CENTEOPOMUS TIRIDIS, Lockington. 



(ROBALO.) 



Head 3 ; depth i^ ; eye 7i in head. D. VIII-I, 10 ; A. Ill, 6 ; scales 

 9-75-15, pores 71. Snout 3i in head, including subopercular flap ; 18 

 scales before dorsal ; gill rakers 4 + 9. Preorbital faintly serrate, becom- 

 ing entire with age. Subopercular flap extending to within 4 to 6 scales 

 of front of dorsal. Maxillary 2* in head, extending to below middle of 

 eye. Preopercle strongly serrate, with coarser teeth at the angle. Body 

 robust, the sides not flattened. Dorsal spines moderate, the third longest, 

 2 to 2i in head ; second anal spine not reaching tip of third, its length 2f 

 in head, quite variable, proportionately longest in the young. Ventral 2 

 in head, reaching more than halfway to anal ; caudal shortish, 11 in 

 head; pectoral 2,*; in head. Air bladder large, with 2 recurved appen- 

 dages anteriorly, each 2 or 3 times diameter of eye. Back greenish, sides 

 dull silvery, the upper fins dusky, the lower paler; ventrals plain yellow- 

 ish, scarcely dotted with dusky ; no yellow on other tins ; lateral line 

 black ; some dusky at base of pectoral and behind second anal spine. 

 Length 2 to 4 feet. Pacific Coast of Mexico ; very common from the Gulf 

 of California to Panama; a valuable food-fish, in all respects similar to 

 Centropomus undecimalis. The only differences we find are the larger 

 size of the appendages to the air bladder and the greater length 

 of the third dorsal spine. Here described from a specimen from Mazatlan. 

 (viridis, green.) 



CetUroponiHs viridis, Lockington, Proc. Cal. Ac. Sci., vii, 1876 (1877), 110, off Asuncion Island, 

 Lower California. (Coll. W. J. Fishek.) 



1516. CENTROPOMUS UNDECIMALIS (Bloch). 

 (KoBALO ; Snook; Brocket de Mee.) 



Head 2f to 3; depth 4 to 4i; eye 7i in head. D. VIII-I, 10; A. Ill, 6; 

 scales 9-75 to 80-15 to 17, pores 60 to 70 ; snout 3i; gill rakers 4 + 9; 18 

 scales before dorsal. Body robust, the sides little compressed, the back 

 not much elevated. Preorbital faintly serrated ; subopercular flap extend- 

 ing to within 4 to 6 scales of origin of dorsal. Maxillary extending to 



