FISHERY BULLETIN: VOL. 87, NO. 3, 1989 



from five widely separated localities with that 

 detected by us in nine trawl samples of northern 

 anchovy taken from the central stock (sensu 

 Vrooman et al. 1981). 



MATERIALS AND METHODS 

 Sardinops sagax 



Collections 



Samples were collected from Giiaymas, 

 Sonora, Mexico (February 1985; Fig. 1, guaym; 

 A^ = 48), Magdalena Bay, Baja CaHfornia Sur, 

 Mexico (May 1984; magda; N = 37), the South- 

 ern California Bight (February-April 1986; 

 Huntington Beach, CA, A^ = 8; San Pedro, CA, 

 A^ = 28; pooled into one sample, socal), 

 Monterey Bay, CA (November 1984; monte; N 

 = 29) and Tomales Bay, CA (December 1984; 

 tomal; N = 5). Whole fish were frozen after 



collection and transported to the Bodega Marine 

 Laboratory where they were kept at -70°C 

 until thawed for morphometric measurements 

 and dissection of tissue samples for electro- 

 phoresis. 



Morphological Characters 



Measurements of the following 12 morpho- 

 metric traits were made on partially thawed 

 specimens using either vernier caliper or 

 mounted millimeter rule: a series of lengths 

 measured from the snout to the 1) end of the 

 hypural bones (standard length), 2) anterior 

 margin of the orbit, 3) posterior edge of the 

 maxillary, 4) posterior border of the supraoc- 

 cipital, 5) posterior edge of the operculum, 6) 

 dorsal-fin origin, and 7) vent, followed by 

 measurements of 8) interorbital width, 9) max- 

 imum head width, 10) minimum body depth, 11) 



40°. 



30" 



120° 



110"- 



FiGURE 1. — Map showing locations of collections for Pacific sardine 

 (solid arrowheads) and northern anchovy (open arrowheads). 



654 



