CCCIV 



with white exists on tlie side. Mouths of the Gauges, IViawaddi, and 

 other huge rivers, ascending far above tidal inlhiencii. 



395. Tetrodon Jtuviali/is, Ham. Bueh. Two imperforate nasal 

 tentacles on either side. Body nearly smooth. Superiorly greenish- 

 yello\v,with vermiculated blaekibh lines, becoming white below : there 

 are also irregular blach sjjots and blotches. Large rivers of India and 

 Burma, far ul)0ve tidal inllucnce. 



896. Telrodonpatoca, Ham. Buch. Bheiiij-puUi, Ooriah : Nya-boo- 

 din, Burm. Au imperforate nasal cavity with a fringed margin. Body 

 Bpiny. Light brown above with whitish siiots, becoming silvery below. 

 Lar"-e rivers of India and Burma, far above tidal reach. 



5«i-cfoM— CHONDROPTERYGII. 



Skeleton cartilaginous : no cranial sutures. Rarely a single 

 gill-opening, as the gills by their outer edges are attached 

 to the skin, and there exists an intervening gill-opening 

 between each : no gill-cover. Three series of valves at 

 the bulbus arteriosus. Optic nerves although united 

 do not decussate. Body with vertical and paired fins, 

 the posterior pair abdominal : caudal with an upjier 

 lobe, Avhich is elongated. Intestines with a spiral valve. 

 Male sex with prehensile organs attached to the vertical 

 fins. Ovaries containing large ova Avhich are fertilised, 

 and in some likewise developed internally. Embryo with 

 external deciduous gills. No air-vessel. 



Order— PL A GIOSTOMA TA. 



Body more or less cylindrical, or depressed : the trunk may or may not 

 pass into the tail. J''rom five to seven gill-opeuini,'S, which may be 

 lateral or inferior. Jaws distinct from the skull. 



Sub-Order—SELACIIOWEI, OR SHARKS. 



Body more or less cylindrical, gradually merging into the tail. 



Gill-openings lateral. 



Family — C A R c n A R 1 1 D ^. 



Tlie snout may be produced longitudinally (Carchiiviina3 or true sliavlcs) : or laterally 

 (ZyiBniiia or Lauimer-lieaded sliarlis). Spiracles absent or present Eye with 

 a uTclitating membrane. A small ]>it may or may not exist above the root of llie 

 tail and a second behind the angle ot tlie mouth may be present or absent. Mouth 

 cres'centic, inferior. Teetli may be erect or oblicjue, with a single cusp, hav- 

 ing sharp, smooth, or serrated edges : or they may be small, the cusps being 

 obsolete : or with one in the centre, or one or two lateral ones : or even obtu.se. 

 The first dorsal fin, destitute of a spine, is placed opposite the interspace between 

 the pectoral and ventral : anal fiu present. 



Genus — C.iBCHARlAS, Mllll. and Ileiife. 

 No spiracles. A pif. above the root of the cauddfiii. Snout longi- 

 tudinally produced. Mouth cresceiitic : the (abial fold or groove rarely 



