Jordayi and Evermann. — Fishes of North America. 2033 



ff. A long barbel at tip of cbin ; snout long (produced into form of a tube, 

 as in Syngnathidcn) ; body subterete, very slender, its plates not 

 spinous. Pallasina, 765. 



AooNlN^: 

 hh. Gill membranes joined to istbmus, with or witbont a narrow free fold bebind. 



j. Tip of snout without free median plate or spine; moutb inferior, lower jaw 

 sliort. 

 A-. Vomer without teeth. 



I. Lower side of snout with no barbels; one pair of spines on tip of 



snout. Leptagonus, 766. 



II. Lower side of snout with barbels. 



m. Gill membranes without barbels; a pair of complex barbels 

 under tip of snout; 1 pair horizontal and 1 pair recurved 

 spines at tip of snout. Lower jaw very weak; teeth feeble, 

 sometimes wanting ; 'plates of body mostly with spines. 



PODOTHECUS, 767. 



nun. Gill membranes with scattered barbels. 



11. Plates of body without prominent spines ; no preocular 



spines. Aqonus, 768. 



nn. Plates of body largely spinous; a pair of preocular 



spines. Stelgis, 769. 



M-. Vomer and, often, palatines with teeth. 



o. Dorsal fins rather long, the rays shortened behind, the last one 

 attached by membrane to the body ; no large life-like spine above 

 eye. 

 p. Plates on body largely spinous ; gill membranes with cirri, 1 

 or more on each brancbiostegal; teeth on palatines ; lower 

 jaw short beneath the long snout.* Averruncus, 770. 



pj>. Plates on body largely unarmed; no teeth on palatines; gill 

 membranes without cirri. Sareitor, 771. 



00. Dorsal fins rather short, the rays scarcely shortened behind, the 

 last one not adnate by membrane behind ; a large knife-Uke spine 

 over each eye ; plates on body largely spinous ; no cirri on gill 

 membranes. Xystes, 772. 



j). Tip of snout with a free terminal plate or spine; teeth on jaws, vomer, and 

 palatines. 

 q. Occiput without distinct pit; 2 pairs of occipital spines; dorsal and anal 

 well developed. 

 r. Lower jaw strongly projecting; lower pectoral rays not much pro- 

 duced; terminal rostral plate with 3 spines. Bathyagonus, 773. 

 rr. Lower jaw not projecting; lower rays of pectorals much produced 

 in adults; anal fin abort, of 6 or 8 rays. Xenochirus, 774. 



qq. Occiput with a deep pit; occipital spines none, or reduced to mere 

 traces ; dorsal and anal very short. 

 s. Body slender, elongate; tail not compressed. Odontopyxis, 775- 



ss. Body short and broad in front; tail compressed teeth. 



BOTHRAGONUS, 776. 

 ASPIDOPHOROIDIN.E : 



aa. Spinous dorsal al)sent; body not compressed, its plates not spinous ; mouth small, 

 terminal; gill membranes free from the isthmus. Aspidophohoides, 777. 



759. PERCIS,t Scopoli. 



Percis, Scopoli, Int. Hist. Nat., 454, 1777 (japonicus). 



Hippocephalus, Swainson, Nat. Hist. Fishes, etc., ii, 272, 1839 {super eiliosxis). 



* Jaws subequal in Agonopsis, a South American genus very close to Averruncus. 

 t Dr. Gill has called our attention to the identity of Fercis with B.i2)pocephalus. 



