606 CALIFORNIA ACADEMY OF SCIENCES. 38 



numerous; suborbital stay directed obliquely downward and back- 

 ward; second anal spine mucb heavier than, and at least as long as 

 the third; body short and deep, back arched; mouth very large; 

 head heavy. All known species with cross bands. 



SEnASTICHTHYS Gill. 



nlgrocinclus, serricep.% rubrivinctus, diploproa.* 

 bb. Lower jaw much projecting; head broad, the skull usually convex; 

 cranial ridges, when present, low; gill-rakers very long and slender; 

 scales usually smooth, few if any accessory scales. Suborbital stay 

 little if at all oblique. 



c. Parietal ridges ending in spines; preocular, supraocular and tym- 

 panic spines well developed. Peritoneum black. 



d. Postocular spine present. Second anal spine usually stronger and 

 longer than third. Symphyseal knob strong, projecting forward. 

 Dorsal low. (Peritoneum black, mandibles and maxillary scaled.) 



ACDTOMENTUM 1 E. & B. 



'Type A. ovalis (Ayres). 



melanoslomus, ovalis, rufus, *alntus, macdonaldi n. sp. nov.= 

 N. /u-origer E. & E., not of J. & G. 

 dd. Postocular spine not developed. 



We have not been able to examine the two species (entomelas and 

 atrovirens) and cannot vouch for their position. 

 cc. Parietal ridges not ending in spines. 



e. Preocular spines well developed. Supraocular and tympanic 

 spines sometimes present. Interorbital wide, convex. Perito- 

 neum black. Approximated edges of sub-opercle and inter-opercle 

 frequently ending in spines. Pri.mospina 2 E. .V 1!. 



Type P. Mystinus (J. & G.) 



The only species (mystinus) is the most variable species of the 

 group, 

 ee. Preocular without spine, skull smooth, without spines. Peri- 

 toneum usually white. 



Sebastosomus Gill. 



flavidus, serranoides, melanops, *ciliatus. 

 ■am. Parietals separated by the supra-occipital. 



f. Cranium with parietal ridges only. Lower jaw much project- 

 ing, entering the profile; a prominent symphyseal knob directed 

 forward. Head broad, convex. Iuterobital convex, nearly 

 smooth. 



Sl.r. \STODES Gill. 

 paucispinis, goodci. 

 Species marked with an asterisk have not been examined in reference 

 to the characters utilized. 



ff. Cranium with many ridges, all ending in spines. 



