POMPANOS OF SOUTH ATLANTIC COAST 



211 



is uniformly rounded. At about 11 mm., the fin 

 margin becomes angular at the tips of soft-rays 

 2-4 or 5 and forms an indistinct lobe. Relative 

 dorsal-fin lobe length increases with increased 

 standard length at about the same rate in all 

 species to a size of about 50 mm. At about 

 10-20 mm., these lengths are about 20% S.L. for 

 T. carolinus and T. falcatus and about 22% S.L. 

 for T. glavAius. By 40 to 50 mm., tlie lengths 

 are about 22-25% S.L. for T. carolinus and about 

 22-29% S.L. for T. glaucus and T. Jalcatus. 

 T. carolinus maintains a dorsal lobe length of 

 about 24-29% S.L. from 50 mm. to above 200 

 nun., where there is a slight increase in relative 

 lobe length to about 27-30% S.L. at 230-260 mm. 

 Above 260 mm. there is a decrease in relative 

 lobe length in T. carolinus, approaching about 

 22% S.L. in the largest specimens. Relative 

 dorsal lobe length increases with increased stand- 

 ard length in T. Jalcatus and T. glaucus to the 

 largest sizes examined — 47% S.L. in the 216.5-mm. 

 T. Jalcatus and 72% S.L. in the 211-mm. T. glaucus 

 (appendix table 2 and fig. 20). 



Table 3. Dorsal and anal soft-ray relation for 74 speci- 

 mens of Trachinotus glaucus. 



t Upper numbers in blocks represent specimens with the indicated combina- 

 tion; numbers in parentheses represent approximate percentage of the 

 sample with that combination] 



Relative dorsal base lengths increased gradually 

 with increased standard length to about 120 to 

 130 mm. in T. carolinus and T. glaucus, and in- 

 crease rapidly in T. Jalcatus to about 70 mm. 

 Below 10 mm., dorsal base lengths are about 

 41%, 43%, and 42% S.L. for T. carolinus, T. 

 Jalcatus, and T. glaucus, respectively. Above 10 

 mm., T. glaucus averages the shortest, and T. 

 Jalcatus the longest relative dorsal base lengths. 

 By about 80 mm., the base lengths for T. carolinus, 

 T. Jalcatus, and T. glaucus are about 53%, 57%, 



and 50% S.L., respectively. Beyond 80 mm., 

 T. Jalcatus maintains a base length of about 

 55-59% S.L., and by 180 mm., T. carolinus 

 reaches its maximum relative base length of about 

 57-58% S.L. The relative length of this part 

 increases with increased standard length through- 

 out the specimens of T. glaucus examined with the 

 211-mni. specimen possessing a dorsal base length 

 55% S.L. (appendix table 2 and fig. 21). 



ANAL FIN 

 Elements 



Trachinotus sp. — At 3.07 to 4.66 mm. the spines 

 are barely discernible. No rays are present at 

 3.07 and 4.0 mm., but 15 soft-ray buds are evident 

 in the 4.66-nim. specimen (figs. 1-3). 



T. carolinus. — Elements II-I, 20 to 23. Gins- 

 burg (1952) examined 346 specimens; 4 had 20 

 soft-rays, 127 had 21, 188 had 22, and 27 had 23. 

 Of 172 specunens examined in this study 8 had 20 

 soft-rays, 63 had 21, 94 had 22, and 7 had 23 

 (table 1). Spines are prominent and soft-rays 

 are developed by about 7 mm., and all but about 

 5 of the soft-rays are segmented (fig. 4). All 

 soft-rays are segmented by about 10-11 mm. 

 (fig. 5). Branching of all soft-rays but the first 

 begins at about 17 mm. and is complete bj' about 

 21 mm. The first soft-ray branches at about 27 

 mm. 



T./aZca<MS.- Elements II-I, 16 to 19. Of the 

 24 specimens examined by Ginsburg (1952) 15 

 had 17 and 9 had 18 anal soft-rays. Of 386 

 specimens examined in this study, 4 had 16 anal 

 soft-rays, 199 had 17, 182 had 18, and 1 had 19 

 (table 2). At 5.0 mm. (fig. 8) the spines are 

 prominent and the individual rays are discernible, 

 but none is segmented. By 6.5-8 mm., all but 1 

 to 5 of the soft-rays are segmented, and by 9 mm., 

 all anal soft-rays are segmented. Branching 

 begins at about 13 mm. and is complete at 18 

 to 19 mm. 



T. glaucus. — Elements II-I, 16 to 18. Gins- 

 burg's (1952) 39 specimens were composed of 4 

 individuals with 16 anal soft-rays, 23 with 17, 

 and 12 with 18. Of 74 specimens examined by 

 me, 3 had 16 anal soft-rays, 52 had 17, and 19 

 had 18 (table 3). All rays but the anteriormost 

 and the posteriormost are segmented in the 7.8- 

 mm. specimen, and segmentation is complete in 

 the 11.8-mm. individual (figs. 14 and 15). Branch- 

 ing has not begun by 19 mm., but is completed in 

 some individuals by about 22 mm. The anterior- 



