FISHERY BULLETIN: VOL. 71, NO. 1 



Table 10. — Frequency distribution of the number of anal rays for the Gulf and 



Atlantic populations. 



Table 11. — Frequency distribution of the number of 

 pectoral rays for the Gulf and Atlantic populations. 



northern Gulf population has a slightly higher 

 average value than the southern Gulf popula- 

 tion for all meristic characters except pectoral 

 fin rays and vertebrae. The southern Gulf has 

 on the average a greater number of pectoral fin 

 rays and vertebrae (Tables 7, 8, 9, 10, 11, 12). 

 In the Atlantic the more southerly populations 

 have fewer vertebrae, pectoral rays, second dor- 

 sal rays, and anal rays and more first dorsal 

 rays than the northern populations. 



Material collected between lat 7° and 20°N 

 in the Atlantic has on the average between two 

 and three (2.5) fewer vertebrae than the ma- 

 terial collected north of lat 21°N. There is very 



little overlap in the range of vertebrae in the 

 northern and southern Atlantic populations. 

 Only 1 of 41 specimens from south of lat 20°N 

 has more than 53 vertebrae and only 13 of 87 

 specimens north of lat 20°N have less than 54 

 vertebrae (Table 12). However, the relatively 

 few specimens collected between lat 16° and 

 20 °N may not be representative of the popula- 

 tion residing there due to sampling error and 

 hence, not represent the true range of vertebrae 

 for that population. 



CONCLUSIONS 



The above data suggest that there is but a 

 single species of Merluccius in the tropical west- 

 ern Atlantic, including the Caribbean and Gulf 

 of Mexico. The Gulf population as a whole can- 

 not be distinguished from the Atlantic popula- 

 tion by means of any of the characters examined. 

 For all of the characters examined differences 

 between both populations are small. Within each 

 area there are local differences in most of the 

 characters ; however, these differences are minor. 

 The Gulf and Atlantic populations have identical 



Table 12. — Frequency distribution of the number of vertebrae for the 

 Gulf and Atlantic populations. 



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