FISHERY BULLETIN: VOL, 77. NO. 1 



The superior opercular spine is present on lar- 

 vae by 9 mm and the inferior opercular spine ap- 

 pears later in larvae —12 or 13 mm. Both spines 

 are present on juveniles. An interopercular spine 

 develops on the edge of the gill cover, usually in 

 larvae >10 mm. A subopercular spine was not 

 present on any of the specimens examined. 



The ridge anterior to the postocular spine is 

 heavily serrated and remains so until preocular 

 spine formation. The preocular appears first as a 

 bump in transforming larvae =16.0 mm long and 

 develops into a spine in pelagic juveniles >19 mm. 



Development of the supraocular follows a similar 

 pattern appearing at about the same time as the 

 preocular. Beneath the eye the fourth spine of the 

 superior infraorbital series is present in larvae >9 

 mm and the third spine of this series is present in 

 all larvae >13 mm. The second superior infraorbi- 

 tal spine never forms. All three superior infraorbi- 

 tal spines disappear by 43 mm. The second spine of 

 the inferior infraorbital series is present on speci- 

 mens >10 mm and the two spines in this series 

 persist in juveniles. The third inferior infraorbital 

 spine never develops. The nasal spine develops 



T.^BLE 9. — Development of spines in the head region of Sebastes pinniger larvae and juveniles. Specimens above dashed line are 

 undergoing notochored flexion. + denotes spine present and - denotes spine absent. 



88 

 8.9 

 9.3 

 9.8 

 10.7 

 10.7 

 10.9 

 12.3 

 123 

 M2.8 

 '13.0 

 '14 1 

 '142 

 '15.2 

 '160 

 '160 

 '16.2 

 '16.8 

 '178 

 '18 4 

 '186 

 M8.9 

 J 19.4 

 M9.5 

 =20.0 

 ■1208 

 =22.4 

 123 4 

 '264 

 =26.4 

 =26 6 

 =28.6 

 =28.8 

 =29.4 

 =30 4 

 =30.9 

 =34.1 

 =38.0 

 =387 

 '39.2 

 =40.0 

 '41 

 =42.4 

 «594 

 *117.7 

 6181 



+ + 



+ + 



+ + 



'Transtorming, 



-'Bump tndicates beginnrnq of spine formation 



^Pelagic luvemle 



■'Spine IS bifid 



^Parietal and nuchal spines fused 



■^Benthic juvenile 



^Spine has become rounded, no sharp tip 



26 



