i94i CATALOGUE OF FISHES OF TORTUGAS 77 



Fish that I believe to be the young of this species accompany floating Sar- 

 gassum. At 115 mm. their color is olivaceous above, golden below; a line of dark 

 brown of width of pupil extending through eye from snout to dorsal origin; 

 body with six crossbands of about the width of the paler interspaces; a yellow 

 line above pectoral base and extending to base of caudal represents the brassy 

 stripe of the adult. 



Fragments of fish, of a length of 100 mm. or a little more, have not been rare 

 in the refuse of the tern colony on Bird Key, and its successor on Long Key. 



W.H.L. 



This fish, which reaches a weight of about 100 pounds, is most readily recog- 

 nized by its elongate body, depth about 3.4 in standard length; by the low 

 anterior lobes of the soft dorsal and anal, which are scarcely elevated except in 

 large examples; and by the small number of gill rakers (10 to 14 on lower limb 

 of first arch). 



Middle Atlantic states to Brazil, also Mediterranean Sea. S. F. H. 



Caranx ruber (Bloch). Runner 



(Plate 2, figure 3) 



A fish of the open water, swift and restless. At Tortugas the commonest of the 

 carangids in summer. Schools of small or medium-sized ones may then be found 

 over any bottom, but large adults are comparatively rare. 



Small ones are taken by the terns in great numbers, several hundred, up to 

 215 mm. in length, having been gathered in the Bird Key rookery. 



This species is a terror to smaller fishes. Young or small scarids and labrids fly 

 from its approach. Schools of the lesser surface fishes, madly dashing and leap- 

 ing, may often be seen between the upper and nether millstones of its and the 

 terns' attack. 



As seen by the diver, it is usually bluish gray, with a median dark blue or black 

 line from the nape becoming visible laterally in advance of the soft dorsal and 

 continuing at its base to the caudal peduncle and thence to the tip of the lower 

 lobe of the fin; a light blue line of half its width runs above it throughout its 

 length. But this pattern is changeable. By day the fish may be more ashen or even 

 slaty in hue. At dusk over clear sand the darker blue stripe may fade out com- 

 pletely. 



In contrast with its usual haste is its leisurely approach where Thalassoma or 

 Anisotremus waits to ease, it seems, each parasite-infested passer-by of its unrest. 

 In slow circles the wheeling school revolves, while here and there individuals 

 with premaxillaries protruded and perhaps with gill covers raised solicit atten- 

 tion. Those that do not receive attention resume their swimming, and offer them- 

 selves again while the group remains or after it makes a brief excursion, vanishes 

 in the gray haze, and returns to gyrate anew. While undergoing inspection the 

 fish wriggle and at last break away and rejoin their fellows, but on the whole 

 seem pleasurably embarrassed by the treatment they received. W. H. L. 



