the frontal system weakens rapidly out to 

 sea from Cape San Lucas. 



If the system is chiefly maintained by rela- 

 tive transports of California Current, Gulf of 

 California, and Subtropical Surface Waters, 

 its most probable position could be determined 

 perhaps by sin-iply studying these water masses 

 throughout the year, after taking into account 

 the geography of the Gulf entrance. 



A review of the CalCOFI data indicates that 

 observations of the Cape San Lucas front, 

 as a particular object of study, are scant 

 (Griffiths, 1965). These data do indicate, how- 

 ever, that the frontal system might be found 

 at almost any time of the year, though it 

 is best developed in spring and summer. 

 It might also be found far from the Cape; 

 sometimes inside the Gulf, though rarely far 

 inside; and sometimes as far north as Mag- 

 dalena Bay, particularly late in the year when 

 ■warm, salty water is known to move north- 

 ward inshore (Reid, Roden, and Wyllie, 1958). 

 It might sometimes be absent. The CalCOFI 

 and our data show that this area is likely to 

 be oceanographically complicated at any time. 

 It would therefore be desirable to continue 

 the study of this area to elucidate seasonal 

 changes. Apart from seasonal changes, the 

 various features of the oceanography of this 

 area should be studied in more detail. In 

 particular it would be helpful to determine 

 whether each kind of water contributing to 

 the area has a distinctive biological regime 

 associated with it, so that changes in these 

 regimes might be related to oceanographic 

 events. 



ACKNOWLEDGMENTS 



Maurice Blackburn gave his encouragement 

 and help; Joseph L. Reid, Jr., provided in- 

 valuable advice; and Edward Bennett and 

 Klaus Wyrtki made helpful comments on the 

 manuscript. 



LITERATURE CITED 



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