Jordan and Evermann. Fishes of North America. 613 



" Scapular arch formed by the proscapula and post-temporal, the latter 

 detached from the side of the cranium and impinging on the supraoccipi- 

 tal. Hypercoracoid and hypocoracoid coalescing in a single lamellar 

 imperforate plate ; actinosts normal. Cranium with the condyle confined 

 to the basioccipital ; exoccipital coalesced with epiotics and opisthotics. 

 Vomer obsolete ; opercular apparatus complete; preopercle slightly con- 

 nected with suspensorium ; suborbitals suppressed; jaw bones com- 

 plete and little aberrant ; palatines and pterygoids well developed ; 

 anterior vertebra* separate; veiitrais abdominal." Air bladder with a 

 duct. The character of having the scapular arch free from the cranium 

 and attached to the anterior vertebrae, shared by these fishes with the 

 eels and several other groups may be, in the different cases, of independent 

 origin, and is probably not indicative of any special affinity. (erepof, dif- 

 ferent ; 4"0f, shoulder.) (Heteromi, Gill, American Naturalist, November, 

 1889, 1016). 



a. Jaws normal; dorsal spines separated; both jaws with teeth. NOTACANTHIDJE, LXXXVII. 

 aa. Jaws forming a suctorial mouth, with modified rami; no teeth. Dorsal spines close 

 together', united by membrane to form a high triangular fin. 



LlPOGENYIDAC, LXXXVIII. 



Family LXXXVII. NOTACANTHID^E. 



Body elongate, somewhat compressed, ending in a band-like, tapering 

 tail. Scales small, cycloid. Dorsal represented by a series of short spines 

 with few or no soft rays. Anal fin of many rays, the anterior ones being 

 spinous; ventrals abdominal, with more than five soft rays, and usually 

 one or two spines. Jaws normal ; mouth inferior, the snout projecting 

 beyond it, the lower jaw meeting the palate as in sharks. Jaws and 

 palatines armed with a series of close-set teeth ; palatines movable ; 

 vomer wanting. A sharp spine more or less hidden by the fleshy folds of 

 the lips at angle of mouth, on each side. Shoulder girdle loosely sus- 

 pended to the skull by ligaments. Air bladder present, with a pneumatic 

 duct.* Gills 4; gill openings wide, not restricted above, the membranes 

 separate, free from the isthmus. Pseudobranchia? absent. Gill rakers 

 long and slender. Ovaries without oviducts. Deep-sea fishes, found in 

 most seas. Genera about 5 ; species about 12. This is an archaic group, 

 and, as already stated, its relationships are still doubtful. (Notacanthi, 

 Giinther, Cat., m, 544, 1861.) 



NOTACANTHIN^E: 

 a. Dorsal spines 6 to 12; teeth in upper jaw compressed and obliquely triangular. 



b. Origin of spinous dorsal far in advance of vent; mouth lateral with the lip continuous. 



NOTACANTHUS, 294. 

 POLYACANTHONOTINjE : 



rtrt. Dorsal spines 27 to 38. Teeth in jaws erect, fine; ventrals separated. 



c. Snout not very elongate, not proboscis-like; dorsal and anal spines low and strong, the 

 latter 50 or more in number; lateral line straight. MACDONAUMA, 296. 



* According to Vaillant; Giinther, however, does not find a duct in Notacanlhus sexspinis. 



