FISHERY BULLETIN: VOL. 70, NO. 1 



B 



^ «.*»>/^^V ;it; 



Jf' *Vt 





■^ 



Figure 3. — Developmental stages of Sphyraena borealis. Specimens A, B, and C were 



laboratory reared; specimen D was collected in a plankton net. A. 9.4 mm SL; B. 



12.3 mm SL; C. 14.5 mm SL; D. 21.0 mm SL. 



in a 10.9-mm SL larva. All specimens had 24 

 vertebrae. 



Six branchiostegals were present on the 7.4- 

 mm SL larva and a seventh had developed on 

 the 9.1-mm SL specimen. Cleithra were present 

 but poorly ossified at 7.4 SL; they were well de- 

 veloped at 9.1 mm SL. 



Ossification of the caudal region began at 

 7.4-mm SL. At this size, the hypural bones were 

 developing and some rays could be distinguished 



in the ventral half of the caudal finfold. All 

 caudal elements were beginning to develop by 

 10.9 mm SL and were easily recognized on a 

 12.1-mm SL specimen. The last three vertebrae 

 (including the urostyle) contributed to support 

 of the caudal fin; both neural and haemal spines 

 of the antepenultimate vertebra (22nd) sup- 

 ported developing accessory rays of the caudal 

 fin, as did the haemal spine of the penultimate 

 (23rd) vertebra. A total of 6 hypural bones 



190 



