YOUNG JACK CREVALLES 



451 



72 mm. fall within my predicted range, but in the 

 lower portion and with loss variation that I 

 encountered. 



Preopercular spines. — Because of the appreci- 

 able individual variation in tins character, it is not 

 possible from the specimens examined to predict 

 accurately at what size the preopercular-angle 

 spine ceases to increase in length — this probably 

 occurs at some size around 7 mm. standard length. 

 Above approximately 10 mm. the length of this 

 spine decreases due to expansion of the posterior 



margin of the preoperculum (fig. 31). This spine 

 is completely absorbed within the preopercular 

 margin between 42 and 47 mm. The numbers of 

 preopercular upper- and lower-limb spines are vari- 

 able but tend to decrease with an increase in stand- 

 ard length (table 1). The preoperculum and the 

 preopercular spines of an alizarin-stained 14-mm. 

 specimen are illustrated in figure 24. 



Pigmentation.' — There are three rows of elon- 

 gated melanophores on the body of the 5.4-mm. 

 specimen — below the base of the dorsal fin, above 



in 



UJ 



H 

 Z> 



o 



CO 



0D 



50 



100 150 200 



STANDARD LENGTH IN MM. 



250 



300 



Figure 29. — Caranx crysos and C. dentex: Relation of the mean number of scutes to standard length. 



