MOBTLA. 



449 



of the pectoral, extended forward, as a horn-like process, from each side. Pec- 

 torals broad, triangular, nol continuous at the side of the head, acute-angled 

 laterally and posteriorly. Ventrals small, between the pectorals. A small 

 subtriangular dorsal on the tail, above and between the ventrals. Tail slender, 

 whip-like. Mouth large, transverse; teeth small, numerous, in pavement. 

 Gill openings large. Eyes lateral. Spiracles moderate, behind the orbits. 



Some of the gigantic members of this family are said to reach a width of 

 twenty feet and a weight of more than four tons. 



Mouth inferior 



cephalic fins directed forward and rolled outward 

 teeth on both jaws .... 

 teeth on the upper jaw only . 

 Mouth anterior 



cephalic fins directed forward 



teeth on the lower jaw only . 



Mobula (page 449) 

 Ceratubalis (page 453) 



Mania (page 454) 



Mobula. 



Mobula Rafinesque, 1S10, Ind. itt. Sic, p. 48, 61. 

 Cephalopterus Risso, 1810, Ichth. Nice, p. 14. 

 Dicerobaliis Blainv., 1816, Hull. Soc. philom., p. 112. 

 Cephaloplera Dumeril, 1865, Elasm., p. 650. 

 Mobula Dumeril, 1865, Elasm., p. 650. 



Head broad, flat, truncate; mouth wide inferior; internarial space wide; 

 rostrum short, broad, sharp edged anteriorly; rostral fins moderate, distinct 

 from the pectorals, directed forward and obliquely downward but rolled from 

 below outward in a subcylindrical roll (much as figured in Raia fabroniana 

 Lacepede, 1800, Poiss., 2, p. Ill, pi. 5, f. 1) when not in use. Teeth on both 

 jaws small, numerous, in pavement. Tail slender whip-like, with or without 

 a serrated spine; dorsal fin between the ventrals. 



With a serrated caudal spine 



tail more than twice as long as body 



teeth bands reaching angles of mouth 

 tail thrice as long as body 



teeth bands reaching the angles 

 Without a serrated caudal spine 



tail one and one half times length of body 

 teeth bands nearly reaching the angles 



mobular (page 450) 

 japanica (page 450) 



eregoodoo-tenkee (page 451) 



