1360 Bidletin ^7, United States National Museum. 



Salema, MARCGRAVE, Hist. Pise., 153, 1648, Brazil. 



Bream, BROWNE, Jamaica, 446, No. 1, 1756, Jamaica. 



Perca unimaculata, BLOCH, Ichthyologia, pi. 308, 1792, Brazil ; on a figure by Prince 

 MAURICE. 



Sparus salin; LACEPEDE, Hist. Nat. Poiss., iv, 136, 1803; based on unimaculatus of BLOCH. 



Sargus humeri-maculatus, QUOY & GAIMARD, Voyage Freycinet, Zool., 297, 1825, Rio 

 Janeiro. 



Sargus flavolineatus, CUVIER & VALENCIENNES, Hist. Nat. Poiss., vi, 60, 1830, Cuba; GUN- 

 THER, Cat. Fishes, I, 446, 1859. 



Gyncedus brama, GRONOW, Cat. Fishes, Ed. Gray, 56, 1854, South Carolina. 



Sargus caribceus, POEY, Memorias, n, 197, 1860, Cuba. 



Grammistes unimaculatus, BLOCH & SCHNEIDER, Syst. Ichth., 184, 1801 ; after BLOCH. 



Sargus unimaculatus, CUVIER & VALENCIENNES, Hist. Nat. Poiss., vi, 62, 1830; GUNTHER, 

 Cat. Fishes, i, 446, 1859; EIGENMANN & HUGHES,* Proc. U. S. Nat. Mus. 1887, 69. 



Diplodus caribceus, JORDAN & GILBERT, Synopsis, 930, 1883. 



Diplodus flavolineatus, JORDAN, Proc. U. S. Nat. Mus. 1886, 42. 



Archosargus unimaculatus, JORDAN & FESLER, I. c., 520. 



1734. ARCHOSARGUS POURTALESII (Steindachner). 



Head 3|; depth 2f. D. XIII, 10; A. Ill, 10; scales 7 or 8-48-15. Pec- 

 toral fin reaching second anal spine ; body rather less deep, the snout a 

 little longer; ventrals shorter, 5 to 5| in head; otherwise essentially as 

 in Archosargus unimaculatus, of which it is the Pacific coast representa- 

 tive. Galapagos Islands, rather scarce, one specimen obtained by the 

 Albatross on Chatham Island. The differences between the pourtalesii and 

 unimaculatus are very slight, and might be ignored were it not for the 

 remote and restricted habitat of the Pacific form. (To Louis F. de Pour- 

 tales, a friend and associate of Agassiz, who was with him 011 the Hassler 

 expedition, by which this fish was discovered.) 



Sargus pourtalesii, STEINDACHNER, Fische Afrikas, 39, 1881, Galapagos Islands. 

 Archosargus pourtalesii, JORDAN & BOLLMAN, Proc. U. S. Nat. Mus. 1889, 186; JORDAN & 

 FESLER, I. c., 521, 1893. 



1735. ARCHOSARGUS TRIDENS (Poey). 



Head more than 4; depth 2^- in total length with caudal; eye 3 in 

 head, 1 in snout. D. XII, 10; A. Ill, 9; maxillary extending to a poin^ 

 between the pupil and the anterior border of the eye. Incisors f on each 

 side. Profile with a slight depression above the eye ; second anal spine 

 much longer than the third. Color grayish, belly white ; 8 golden longi- 



* The specimens examined by Eigenmann and Hughes, now before us, differ decidedly 

 in the proportions, the color, and the size of the teeth ; but while the differences of the 

 extremes are very marked, the intergradation is so perfect that no tangible specific dis- 

 tinctions can be made out. We have only the deeper form (flavolineatus) from Key West, 

 while we have both extremes from Havana. So far as we are able to judge from the 

 figures and the descriptions, the unimaculatus of JBloch & Schneider, Cuvier & Valen- 

 ciennes, and Jordan & Gilbert, the caribceus of Poey, and the humeri-maculatus Quoy & 

 Gaimard, represent the more slender form, while the flavolineatus Cuvier <fc Valenciennes 

 represents the deeper form. The differences of the extreme forms seem to be these: 

 The deeper form (flavolineatus): 



Greatest depth, 2 in length. 



Ventral outline very much rounded. 



Distance from insertion of first dorsal 

 spine, obliquely to snout, 1 in depth. 



Teeth about narrower than in the more 

 slender form. 



Body more compressed. 



The more slender form (unimaculatus): 

 Greatest depth, 2i in length. 

 Ventral outline almost straight. 

 Distance from insertion of first dorsal 

 spine, obliquely to snout, 1 in depth. 



