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Fishery Bulletin 97(4), 1999 



applied in our study (Tables 4 and 5); the results show 

 that there are significant differences in growth be- 

 tween males and females for M. cephalus and M. 

 curema . Oren ( 1981) mentioned: "sometimes the fe- 

 males grow slightly faster (Thomson, 1951; Hickling, 

 1970); Cech and Wohlschlag, 1975), live longer than 

 the males (Thomson, 1951) or at least are predomi- 

 nant among older fish (Hickling, 1970)." 



In general, the values of the relationship between 

 length and weight obtained in our study are very 

 similar to those expressed by other authors for coastal 

 lagoons and marine areas. The results obtained for 

 M. cephalus are similar to those shown by Kesteven 

 (1942), Morovic (1954), Marquez (1974), Serbetis 

 (1939), and Ezzat (1965). In the same way, the re- 

 sults obtained for M. curema are similar to those 

 shown by Angell (1973) and Richards and Castagna 

 (1976). 



The longevity values for M. cephalus in different 

 localities are given in Table 6. The highest values, 

 57.6 and 49.9 years, were found in the marine zones 

 by Ilin ( 1949) in the Black Sea and Kesteven (1942) 

 in Australia, respectively. The lowest values were 

 obtained by Broadhead (1958), 3.7 for males and 4.5 

 years for females of this species in the marine zones, 

 and by Heldt (1948), 4.6 years in coastal lagoons. 



The values of longevity for M. curema in different 

 areas are shown in the Table 7. The highest value 

 was obtained by Alvarez (1979), 30 years in Cuba, 

 and the lowest by Richards and Castagna ( 1976), 3.8 

 years in Virginia. 



The longevity values obtained in the study, 28.3 

 and 18.7 years for M. cep/!o/!vs and M. curema. re- 

 spectively, showed an intermediate position in rela- 

 tion to the values found by other authors. In all cases, 

 as Taylor (1958) has shown, the longevity and 



