3 906.] FJiESH-WAtER FISHES OF TRINIDAD. SSl 



2. Two dorsal fins. 



a. Anterior dorsal of 4 spines. 



a. Jaws with bands of small pointed teetli. 



28. Agonostomus nionticola. 

 /8. Jaws with minute ciliiform teeth * ; anal lin 

 usually with III 8 rays; 32 to 36 scales in a 

 longitudinal series. 

 Second dorsal with a series of small scales behind each ray, other- 

 wise naked 29. Ifitffil brasilicnsis. 



Second dorsal covered with small scales 30. M. tricliodon. 



b. Anterior dorsal of 7 or 8 spines ; anal with 3 spines, 



the second and third strong f. 



65-75 scales in a longitudinal series; second and third anal spines 



subequal 31. Centropomiis imdecimalis. 



50-60 scales in a longitudinal series ; second anal spine consider- 

 ably longer than third 32. G. ensiferus. 



c. Anterior dorsal of 6 or 7 slender flexible spines; 



anal with a single feeble spine %. 

 Vomer toothed ; lower jaw projecting ; scales small. 



37. Philijpnus dormitator. 

 Vomer toothless ; jaws equal anteriorly ; scales rather large. 



38. Dormitator maculatus. 

 B. Ventrals united to form a disc. 



1. Jaws with bands of small pointed teeth and an outer 



series of larger teeth. 



32 scales in a longitudinal series 39. Gobius fasciatus. 



60-75 scales in a longitudinal series 40. Chonopkoriis banana. 



2. Teeth in the jaws in a single series 41. EoortJwdus breviceps. 



* Although only Jf. brasiliensis and TUf. tricliodon have been actually recorded 

 from Trinidad, there can be but little doubt that all the species of Mugll which occur 

 on the Atlantic coasts of America are to be obtained there. 



These may be distinguished as follows : — 



I. Second dorsal naked except for a series of small scales behind 



each ray ; anal with III 8 rays (rarely III 7 or III 9). 



38 to 42 scales in a longitudinal series cepJialus L. 



32 to 36 scales in a longitudinal series brasiliensis Ag. 



II. Second dorsal covered with small scales. 



A. Anal with III 9 rays (rarely III 8). 



42 to 45 scales in a longitudinal series incilis Hancock. 



36 to 39 scales in a longitudinal series curema C. & V. 



B. Anal with III 8 rays (rarely III 7 or III 9) ; 32 to 36 



scales in a longitudinal series tricliodon Poey. 



f Probably all the Atlantic species of Centropomus occur in the rivers of Trinidad. 

 They may be distinguished thus : — • 



I. Anal with III 7 rays, the second and third spines subequal. 



pectinatus Poey. 



II. Anal with III 6 rays. 



A. Second and third anal spines subequal; 65 to 75 scales 



in a longitudinal series undecimalis Bl. 



B. Second anal spine longer than third. 



75 to 90 scales in a longitudinal series parallelus Poey. 



50 to 60 scales in a longitudinal series ensiferus Poey. 



I Allied to Fliilypnus dormitator and certainly to be found in the rivers of 

 Trinidad are two species which may be distinguished thus : — 



Vomer toothless ; lower jaw projecting ; scales small. 



Dorsal with VI, I 8 rays Elcotris piso7iis Gm. 



Dorsal with VII, I 10 rays E. <juavina C. & V. 



