42 



PISCES 



CLASS I 



Cydohatis, Egerton. Disk circular or oval, and tail very short, without 

 median fins. Rays of paired fins few and well-spaced, the pectorals united in 

 front of the head. Pelvic arch with very large pre-pubic processes. C. oligo- 

 dadyliis, Egerton, from Upper Cretaceous, Hakel and Hajoula, Mount Lebanon. 



Puija, Cuv. (Adinobafis, Ag.), (Fig. 2). Upper Cretaceous (Mount Lebanon) 

 to Eecent. Dermal tubercles of existing i?. davata, Linn., in Pliocene Crags 

 of Noi'folk and Suffolk. 



Family 10. Torpedinidae. Miiller and Henle. Torpedoes. 



Trunk miidi depressed, forming a broad and rounded dish with the pedoral fins, 

 whidh do not extend forwards to the broadly rounded anterior end of the head. Tail 

 short and fleshy, with well-develojjed dorsal and caudal fins. Skin naked. An 

 eledrie organ hehoeen the pedoral fins and the head. Eocene to Recent. 



Torpedo, Dumeril {Narcobatis, Blv.). Sometimes supposed to be represented 

 by skeletons in L'pper Eocene of Monte Bolca, but doubtful. Recent. 

 Narcine, Henle. Upper Eocene of Monte Bolca, and Recent. 



Family- 1 1 . Trygonidae. Miiller and Henle. Sting-rays. 



Trunk mudi depressed, forming a disk with the very broad pedoral fins, which 

 meet in front of the snout, and constitute the anterior border of the head. Tail very 

 slender, sharply separated from the disk, the dorsal fins usually replaced by several 

 stout imbrirating spines of vasodentine, which are antero-jyosteriorly compressed and 

 armed with a row of recurved hooklets on each lateral border. Teeth sm,all, rhombic 

 or polygonal, with bifurcated roof, and forming a close pavement. Skin naked, with 

 large conical plates of vasodentin^, sometimes fused into groups, usually raised into a 

 short spine. Tertiary and Recent. 



Trygon, Adanson {Trygonobatus, Blv. ; Alezandrinum, Molin), (Figs. 83, 84). 

 Tail elongated, with long, flattened dorsal spines. Dermal plates of very 



variable form and size. T. gazolae, Ag. ; T. 

 {Alexandrimim) molini, Zigno ; T. zignoi, Molin, 

 known by nearly complete skeletons from the 

 LTpper Eocene of Monte 

 Bolca. Isolated dermal 

 plates (Fig. 84) have 

 been described as refer- 

 able to Baja, Acipenser, 

 Dynatobatis, Larrazet, 



Fic. .S3. 



Tryijim ruijiifus, Probst. Tooth, an- 

 terior (.-I), posterior (/i), ami lateral (C), 

 aspects, enlarged, and tlie same nat. size 



p^rLt!?'""^'"^"""^- ^'*""""''" ^^""^ and Acanthobatis, Larr 



H. L'pper Eocene 



Taeniura, Urolophus, 

 (Monte Bolca) and 



M. and 

 Recent. 



Xiphotrygon, Cope (Heliobatis, Marsh). Resembling 

 Trygon, but teeth cuspidate. A', acuti-dens, Cope, known 

 by complete skeletons from Eocene Green River Shales 

 of AYyoming. 



Oncobatis, Leidv. Dermal tubercles. Pliocene ; Idaho. 



Fig. «4. 



Tryrim) {Aa< nthohatis) tuher- 

 cidos'ii's, Probst, sp. Dermal 

 tubercle, nat. size. Miocene 

 (Molasse) ; Baltringen. 



