426 DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



The total length of tbe specimen is 59 lines, ofwliicli the head makes 7, and the head 

 and trunk together 17. 



This species was ]ti(ked np in mid-ocean in the South Atlantic, and was purchased by 

 tbe British Museum from the Godeffroy Collection. 



Order HETEROSOMATA. 



Cranium posteriorly normal; anteriorly with twisted Aertex, to allow two orbits on the 

 same side, or one vertical and one lateral; basis cranii not quite simple. Dorsal fin long, 

 of jointed rays. Superior pharyngeals 4, the third longest, much extended forward, the 

 inferior separate. (Cope.) 



Family PLEURONECTIDyE. 



/ Phronetti, Rafinesqur, Inilice (V Ittiologia Siciliana, 1810, 14. 



rieuroneciida; Fleming, British Animals, 1828, 178. — Bonaparte, Catalogo Metodico dei Pesci Europei, 

 1846, 47.— SwAiNsoN, Nat. Hist. Fishes, ptc, 1839, ii, 187.— Gunther, Cat. Fish. Brit. Mus., iv, 39!t.— 

 Gill, Arr. Fam. Fiah., 1872, 2, (No. 15).— Jordan and Gilbert, Bull, xvi, U. S. Nat. Mus., 813. 



Pleuronecieoidei, Bleeker, Teutamen, 1859, xv. 



Body strongly compressed, more or less oval or rhomboid, and with one of its sides 

 (which is upward when the animal is reclining on its side) colored, and the other (which is 

 dowuward) generally colorless; the scales are variously developed (sometimes ctenoid, 

 sometimes cycloid, and sometimes wanting) ; the lateral line is coutiiuuius behiud ; the head 

 compressed, more or less rhomboid, and with the snout pointed; both eyes are on the same 

 side, one being on or near the forehead, tlie other comparatively low down; opercula 

 normal, unarmed, not concealed by skin ; mouth terminal, and with an oblique lateral cleft and 

 of various extent; branchial apertures continuous below; branch iostegal rays 5 to 8; dorsal 

 elongated, extending generally from about the rostral region to near the caudal fin; anal fin 

 al.so elongated, and extending about as far back as the dorsal; both are composed almost 

 solely of articulated rays; caudal tin distinct from the dorsal and anal; pectorals on both 

 sides; ventrals jugular. The skeleton has numerous vertebrie; pyloric cieca are generally 

 developed, but in small number. 



KEY TO THE SUBFAMILIES AND DEEP-SEA GENERA OF PLEUEONECTID.^. 

 (From Gill & Jordan, modified.) 



I. Mouth small ; sujnamasillaiy ending before or under front of eye; teeth largest on blind side. 



Pleuroneciinm 

 A. Teeth iu one series. 



1. Teeth rather large, bluutish or trenchant: eyes dextral (sometimes sinistral in one species); 

 ventrals (usually) both lateral, 

 n. Dorsal tin with less thau 80 rays; aual with less than 60. Eyes dextral. 



Lateral Hue not arched. Scales not imbricated, usually ctenoid iu male, cycloid in female. 



Pleuronectes 



Lateral line arched anteriorly. Scales ctenoid Limanda 



6. Dorsal fin with more than 95 r.ays; anal with more than 80; body unusually elongate. 



Left side of skull with strong mucous cavities. Lateral line nearly straight. Anal spine 



present. Eyes dextral Glyptocephalus 



Mucous cavities not present. Caudal subsessile; left pectoral only present; lateral liue 

 present, arched on eyed side, straight on blind side. Eyes sinistral. 



MONOLENE 



II. Mouth large, 8ui>r:iinaxillari(s end under eye; ventrals lateral; vomer aud palatines toothless. 



Uipjwglossinw 



A. Caudal I'm lunate. 



1. Lateral liue arched in front; scales cycloid Hippoglossus 



2. Lateral line not arched. 



a. Teeth not arrow-eliapod ; gill-rakers few, short Platvsomatichthvs 



B. Caudal fin not lunate, the middle rays produced. 



1. Lateral line arched in front; body usually sinistral. 



a. Dorsal fin single Paralichthys 



b. Dorsal in two parts, its anterior rays, as well as sinistral ventral, niucli prolonged. Scales 



cteuoid Notosema 



2. Lateral lino not arched. Body dextral lllproULOSSOlDES 



