164 



University of Washington Publications in Biology 



[Vol. 2. 



a large symphyseal knob, directed forward; peritoneum white or 

 with dark dots; depth about 2> 2 /t, length; anal rays III, 9; color 

 light olivaceous-red ; young olivaceous, somewhat mottled. Range : 

 Barclay Sound, B. C., to San Diego. Marine. Common southward. 

 Bocaccio. Grouper 180. Scbastodcs paucispinis (Ayres) 



Fig. 41. A view of the dorsal 

 side or top of the head of a rock- 

 fish, Sebastodcs, showing the ar- 

 rangement of the cranial spines 

 and ridges. Cor — coronal spine; 

 Nas — nasal opening; Nas Sp — Orb- 

 nasal spine; Hum — humeral 

 spines; Nuch — nuchal spine; 

 Parie — parietal spine or ridge; 

 Pre Sp — preocular spine; Post — - 

 postorbital spine; Supra — supra- 

 ocular spine; Sym — symphyseal 

 knob; Tym — tympanic spine. 

 Drawn by Arthur D. Welander. 



— How 



5b. Parietal bones usually meeting; mesethmoid processes better de- 

 veloped, straight, not elevated; smaller symphyseal knob. Fig. 41. 



6a. Peritoneum white to dusky; dorsal fin deeply emarginate. 



7a. Body usually more slender (depth in adult 2.9 to 3.5 in stand- 

 ard length) ; snout sharply pointed; symphyseal knob conspicu- 

 ous; lower jaw strongly and sharply projecting; pectoral rays 

 17 or 18 (rarely 19 in fiavidus) ; dark specks on body few and 

 relatively inconspicuous, and not extended onto the dorsal fins ; 

 light blotches near base of dorsals well developed ; caudal 

 fin more or less yellow ; anal fin truncated ; unbranched pector- 

 al rays less thickened than in melanops; no light band along 

 mid-sides; size moderate, usually less than 15 inches long; 

 adults living offshore ; young not normally inhabiting the tide 

 pools. 



8a. Tips of nasal spines concealed (except rarely) ; occipital 

 ridges very inconspicuous ; spinous dorsal long and low 

 (highest spine 2.8 to 3.0 in head) ; dorsal soft rays 15 or 16; 

 anal 9, rarely 8; pectoral 17 or 18, usually 17; unbranched 

 pectoral rays 8 or 9, usually 8 ; body usually more slender 

 (depth 3.2 to 3.5), and anterior profile less steep; profile of 

 snout more arched ; upper profile of symphyseal knob form- 

 ing an angle of about 45° with horizontal axis; eye smaller 

 (in adults about one foot long 1.3 in snout, 1.2 in interorbital 

 and 4.5 in head) ; color much darker, blackish olive on head 

 and back ; dark specks on body difficult to discern ; light 

 blotches along dorsal base usually more conspicuous ; vertical 

 fins not margined with blackish ; caudal fin blackish olive- 

 yellow. Range : California, from San Francisco to Mexican 

 boundary. Marine. Common. 

 181. Scbastodcs scrranoides Eigenmann and Eigenmann 



