HOUDE: NORTHERN SENNET 



D 



Figure 2. — Developmental stages of Sphyraena borealis reared in the laboratory. A. 

 3.8mmSL; B. 4.3 mm SL; C. 5.3mmSL; D. 7.4 mm S.L. 



Keeled Scales 



Keeled scales appeared along the lateral line 

 on the caudal peduncle when specimens were 

 about 14.5 mm SL (Figure 3C). 



Osteology 



Ossification of the axial skeleton proceeded 

 from the cephalic region caudad as growth 



occurred. A 7.4-mm SL specimen appeared to 

 have nearly complete skeletal development of the 

 head region, but little development posteriorly. 

 Vertebral development was restricted to incom- 

 plete neural and haemal arches in the 7.4-mm 

 SL larva. Centra were forming in a 9.1-mm SL 

 larva and appeared to be completely developed 



189 



