ACANTHOPTERYGII. 233 



bial. Merluccius Cuv. M. vulgaris Flem. hake ; PseudopTiycis, Lotella, 

 Physiculus, Uraleptus, Laemonema ;Phycisft\. Sch., Ph. blenntoides Bl.-Sch.; 

 Haloporphyrus (Lepidion) and Antimora abyssal ; Lota Cuv. f . w., L. vulgaris 

 Cuv., the burbot or eel pout, in some English rivers ; Molva Nilss. M. 

 vulgaris Flem. the ling ; Motella Cuv., rock-lings ; M. mustela Nilss., M. 

 cinibria Nilss., M. tricirrata Nilss., M. macro phthalma Gthr. ; Raniceps 

 Cuv., R. raninus ; Bregmaceros ; Brosmius Cuv., B. brosme the torsk ; 

 Theragra, Eleginus Fischer. Muraenolepis without separate caudal fin 

 may be placed here. 



Sub-order 10. ACANTHOPTERYGII. Spiny-rayed fishes. 



Anterior vertebrae unmodified : anterior rays of dorsal and 

 anal fins typically simple or spinous, but all the fin-rays are some- 

 times jointed. The lower pharyngeals are generally separate. 

 Air-bladder if present typically without pneumatic duct in 

 the adult. Border of upper jaw formed by premaxillary. Sup- 

 raoccipital in contact with frontals. Shoulder girdle attached 

 to skull by post-temporal. No mesocoracoid. Opercular appar- 

 atus complete ; gill-openings in front of the pectorals. Pelvic 

 fins more or less anterior, normally attached to the 

 shoulder-girdle, typically with 1 spine and 5 rays. The 

 great majority of marine fishes belong to this section. They 

 differ widely among themselves and some of them approach 

 closely to the sub-orders previously described. A certain number 

 of the tribes can be clearly defined, but many of them include 

 forms so diverse that they defy concise definition, and can only 

 be described as centres of relationship. 



Tribe 1. PERCIFORMES, Perch-like fishes. 



No bony stay for the preoperculum. Basis cranii double. Spinous 

 dorsal usually well developed. Pectoral arch with well-developed scapula 

 and coracoid, the former pierced by a foramen or fenestra ; somactids 

 longer than broad, more or less hour-glass shaped, four or five in number, 

 one or two of which are in contact with the coracoid. Pelvics thoracic. 

 Rays of the caudal fin not strongly forked at the base, hypural usually 

 with a basal spine or knob-like process on each side. 



This group is incapable of concise definition. It includes fishes of 

 divers habits and forms. " The division into families, capable of rigid 

 definition is a task of considerable difficulty, and the necessities of a 

 linear arrangement result in the breaking up of some natural sequences." * 



Fam. 62. Berycidae. Body compressed, covered with cycloid or 

 ctenoid scales ; head with large muciferous cavities covered by the skin ; 

 pelvics thoracic, with one spine and more than five soft rays ; with pseudo- 

 branch and numerous pyloric caeca ; air-bladder with pneumatic duct 

 in Beryx and Holocentrum ; mostly deep-sea fishes, many extinct species. 



* Boulenger, in Cambridge Natural History. 



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