YOUNG JACK CREVALLES 



421 



INTERNEURAL AND INTERHEMAL SPINES 



The interneural and interhemal spines 

 (pterygiophores) of at least the five common 

 Atlantic species of Caranx possess posterior lateral 

 projections. These are discernible in illustra- 

 tions by Hollister (1941) in a lateral -view from 

 stained and cleared specimens of ruber (p. 43, 

 fig. 19) and lotus (p. 44, fig. 20). 



Within certain size ranges in two of the species 

 (latus and hippos) these projections extend above 

 the dorsal surface of the body along both sides 

 of the soft-rays of the dorsal and anal fins. They 

 are similar to fin spines in appearance, although 

 not so pointed, and are covered by little, if any, 

 epidermis. None of the other five species studied 

 had these projections protruded or extended 

 above the body surface. 



CAUDAL FIN 



Description.- — The principal rays extend to the 

 posterior margin of the fin — the most-dorsal prin- 

 cipal ray and the most-ventral principal ray are 

 the only two that remain unbranched. The sec- 

 ondary caudal rays also remain unbranched. 



Counts. — The count is given as principal rays 

 above the median line plus those below. The 

 number of secondary rays was determined on 

 only a portion of the specimens examined. 



Urostyle. — Described as visible in normally pre- 

 served specimens. 



PECTORAL AND PELVIC FINS 



Counts. — Counts were made of the fins on one 

 side only, usually the left. Each fin contained 

 one spine plus a number of soft-rays. The spines 

 of the paired fins were similar in construction to 

 each other and to the spines of the dorsal and 

 anal fins. 



Lengths. — Measurement of the longer of each 

 of the paired fins was recorded if the lengths 

 varied. Each fin was measured from the insertion 

 of its spine to the tip of the longest ray, with the 

 fin against the body. 



BODY DEPTH 



Depth at pelvic. — Measured as the distance 

 between the ventral midline of the body at the 

 insertions of the pelvic fins and the origin of the 

 first dorsal spine. 



Depth at first anal spine. — Measured as the 



distance between origin of the first anal spine 



and origin of the spine of the second dorsal fin 



(the ninth dorsal spine.) 



Description. — Both depths are near-vertical. 



The depth at pelvic is more subject to distortion 



by stomach contents, but is preferable to depth 



at the first anal spine, which has a more anterior 



location with respect to the spine of the second 



dorsal fin at lengths of more than 50 to 70 mm. 



standard length. 



HEAD 



Length. — Measured from the tip of the snout 



to the posterior edge of the fleshy portion of the 



operculum. 



EYE 



Diameter. — Measured as the maximum diameter 

 from the anterior to the posterior inner margins 

 of the circumorbitals. 



SNOUT 



Length. — Measured as the least distance from 

 the tip of the snout to the anterior inner margin 

 of the circumorbitals. 



GILL RAKERS 



Counts. — Gill-raker counts were made on the 

 first arch, usually on the left side. A gill raker 

 located at the junction of the upper and lower 

 limbs was included with the count for the lower 

 limb because the major portion of its base origi- 

 nates on the lower limb, and its inclusion facilitated 

 the correlation of the numbers of upper- to lower- 

 limb gill rakers. Rudimentary gill rakers (tuber- 

 cles or very-shortened gill rakers) occurring at the 

 origin of either limb were included in the total 

 count for that limb. These rudimentary rakers 

 are less definitive on larger specimens, but they 

 could be accurately counted on the largest sizes 

 of each species that were examined (up to 830 

 mm. standard length on hippos). Gill-raker 

 counts on specimens less than 20 mm. were not 

 included in the tables, although specimens be- 

 tween 14 mm. and 20 mm. apparently have formed 

 the adult complement. Relation of the numbers 

 of upper- to lower-limb gill rakers is used to 

 show that they apparently are intraspecifically 

 correlated. 



SCUTES 



Definition. — In Caranx, the term "completely 

 developed scute" defines a modified scale situated 



