LAROCHE and RICHARDSON: DEVELOPMENT OF LARVAE AND JUVENILES OF ROCKFISHES 



ent in all specimens examined. The supracleithral 

 spine appears by ~8 mm and is present as a sharp 

 spine on all larger specimens. The superior post- 

 temporal spine appears as a blunt bump at =17 

 mm and is present as a sharp spine on all speci- 

 mens >19 mm long. The cleithral spine appears as 

 a blunt bump at =20 mm and is usually present as 

 a sharp spine in specimens >23 mm. 



Scale Formation . — Lateral line organs, indicated 

 by a row of light colored spots on the flesh, are 

 visible on the smallest larva and most larger lar- 

 vae before scales form. Developing scales are visi- 

 ble on unstained specimens at 19.6 mm in the 



region above the pectoral fin, near the posttem- 

 poral and supracleithral spines. The body is scale 

 covered by =30 mm. 



Pigmentation. — The smallest S. zacentrus larva 

 has melanistic pigmentation on the head over the 

 brain, inside the tip of the lower jaw, and along 

 the anteroventral margin of the maxillary. 

 Melanophores are densely concentrated on the 

 dorsal surfaces of the gut and are present in lesser 

 concentrations on the body wall over the gut cav- 

 ity. Four small melanophores are present along the 

 ventral midline of the caudal peduncle. The pec- 

 toral and pelvic fin membranes are covered with 



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