FISHERY BULLETIN: VOL. 70, NO. 3 



Figure 4. — Juveniles of Sebastes macdonaldi. A. A 40.2-mm pelagic juvenile (LACM 8821-9) collected by mid- 

 water trawl in the Gulf of California. B. A 62.1-mm demersal juvenile (SIO 65-227) collected by otter trawl near 

 Point Tosco, Baja California. 



full complement of five ossified rays is present 

 in each fin in a 9.4-mm stained specimen. Like 

 the pectoral fins, the densely pigmented pelvics 

 elongate gradually throughout the larval period. 

 Pelvic fin length increases from 4% of the body 

 length at the initiation of notochord flexion to 

 10^/f at its completion. Following flexion, it in- 

 creases gradually to a maximum of 18 to 219^ 

 of the body length in larvae 15.0 to 16.0 mm long. 

 In pelagic juveniles pelvic fin length is 21 to 22% 

 of the body length. 



The caudal-fin anlage first appears in larvae 

 about 5.0 mm long as a ventral thickening near 

 the tip of the notochord. The cartilaginous hy- 

 pural elements begin to diflferentiate when the 

 larvae are about 6.0 mm (Figure IB) and the 

 maximum number of three superior and two in- 

 ferior hypurals is present at about 8.0 mm. Os- 

 sification of these elements begins in larvae about 



8.5 mm long and all hypurals, except the slender 

 dorsal-most element of the superior series, are 

 ossifying in a larva 9.2 mm long. Fusion accom- 

 panies further ossification in the superior series; 

 in the largest larva the two larger superior ele- 

 ments have nearly fused into a single plate, while 

 the slender uppermost element remains separate 

 and has just started to ossify. In the inferior 

 series the larger upper element has two centers 

 of ossification which produce a solid calcified 

 plate in the largest larva. The slender lower- 

 most element is also well ossified but remains 

 separate. Thus, larvae of 15-mm length have 

 achieved the adult complement of two superior 

 and two inferior hypurals. The principal caudal 

 rays begin to ossify in 7-mm larvae (Table 2). 

 Ossification proceeds dorsad in the superior 

 series, above the midline of the fin, and ventrad 

 in the inferior series; the adult complement of 



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