48 ACANTHOPTERTGII. 



spine the longest, J-| the length of head. Anal III 7 ; second and third spines of equal length or the 

 second slightly the'shorter, 4-i the lengtli of the fish. Pectoral ^ or a little more than h the length of 

 head. Ventrals extending to or he)'ond the vent, which is nearly eqnidistaiit from hase of inner ventral 

 ray and origin of anal. Caudal peduncle U-l.f as long as deep. Silvery, hack darker; lateral line 

 hlack : spinous dorsal and memhranc hetwecn second and third anal spines hlackish ; ventrals dusky at 

 the tips. 



Jlah. Pacilic Coasts of Tropical Ameiicn, cnteriuo; rivers: 



Mexico, Guaymas^ Mazatlan*, San Juan Lagoon S; Gnatemala, Chiapam ' - ' 



{Salvin) ; Panama -^ 



Here described from seven specimens, 200-360 mm. in total length, from Chiapam 

 and Panama. 



C. medins is the Pacific Coast representative of C. pedinatus, fiom which it scarcely 

 deserves to be specifically separated. The scales are less numerous and less crowded 

 anteriorly above the lateral line, the paired ridges on the head are weaker and further 

 apart, and the fin-spines usually more slender than in C. jiectmatns. The black 

 lateral line also appears to be a characteristic feature of the Pacific Coast form. 



3. Centropomus parallelus. 



Centropomus inidechiialis (part.), Gtiuth. Cat. Fisli. i. p. 79 (185'J) \ 



Centropomus jjaralle/us, Voex, Mem. Cul)a, li. p. 120 (186U) ', and Kepert. ii. p. 280 (1868)'; 



Giiutli. Trans. Zool. Soc. vi. 18G8. p. 407'; Vaill. & Boc. Miss. Sc. Me.x., Poiss. p. 22 



(1874) ■'; .lord. & Everm. Bull. U.S. Nat. Mus. xlvii. 1896, p. 1122". 

 Cciitropomvs ajtpendiculaius (part.), Giinth. Trans. Zool. Soc. vi. 18G8, p. 40G'. 

 ('cntropu)nus niexicanus, Bocourt, Ann. Sc. Kat. (5) ix. 18C8, p. 90"; Vaill. & Boc. o. c. p. 23, 



t. ]. fig. 2"; Jord. & Everm. t. c. p. 1121 '" ; Meek, Pbl. Columbian Mus. Zool. v. 1904, 



p. 199". 

 Centropomus parallelus (part.), Boulciig. Cat. Fish. i. p. 3C9 (189.5) '". 

 Ceiitropornus yahhi, Fowler, Proc. Ac. PLilad. 190G, p. 423, fig. 1 ''. 

 Centropomus Iteringi, Fovifler, t. c. p. 425, lig. 2^'. 



Depth of hody ahout 3| in the length, length of head 2;}-2|. Snout IJ-li as long as eye, the diameter of 

 which is 4g-6 in the leugtli of head ; interorbital width 7i in the length of head. ]\Iaxillary extending 

 to helow middle of eye, its greatest width 5-?- the diameter of eye. Pra^-orbital acutely serrated ; 

 prccoperculum acutely serrated, with 2 or 3 enlarged serrno at the angle; praiopercular ridge with 2 spines 

 at the angle. Opercular flap extending to the vertical from the origin of dorsal. 14 gill-rakers, 

 including 2 or 3 rudiments, on the lower part of anterior arch. 75—^8 scales in a longitudinal scries, 

 8-11 between middle of second dorsal and lateral lino. Dorsal VIH, I 10 ; third or fourth spine longest, 

 1 the length of head. Anal 111 6 ; second spine a little longer than third, aliout \ the length of the 

 tish. Pectoral a little mui'e than ,', the length of head. Ventrals about reaching the vent, which is 

 situated very slightly Jiearer to the origin of anal than to the base of the inner vi'Utral rays. Caudal 

 peduncle about 1.] as long as deep. Silvery, Ijack darker; lateral line usually more or loss blackish ; 

 dorsal fins dusky. 



Ilab. Atlantic Coasts of Tropical America, entering rivers: 



Mexico, Oaxaca^'", ,San Francisco", lioca del Kio^', El Hule i^, Perez i\ 

 and the liio Tonto [Gadow) in Vera Cruz ; Panama, Eio Chagres [Salvin^). — 

 Surinam '* ; Brazil, Pernambuco ^-, Bahia ' ^- ; Cuba - ■' ; Haiti '^ i- '^ . Jamaica * ^-. 



