VERTEBRATA (CHORDATA). 



91 



T?ig. 81. A, Spinax acanthias, one of the Dog-flshes ; B, Chimcera monstrosa ; 

 c, Tail-spine of an Eagle-Ray (MyHobatis). 



ORDER VI. DIPNOI. 



Sub-ord. 1. Sirenoidei. 



Fam. a. Lepidosirenidse. Lepidosiren, Protoptems. 

 Fam. 6. Ceratodidse. Ceratodus (" Jeevine "). 



Sub-ord. 2. *Ctenodipterini. Dipterus, Ctenodus. 



(Hyrtl, Lepidosiren paradoxa, Monographic, Prag, 1845 ; Owen, Descrip- 

 tion of the Lepidosiren annectens, Trans. Linn. Soc., 1840 ; Gunther, De- 

 scription of Ceratodus, Phil. Trans., 1872 ; Huxley, Structure of Ceratodus, 

 Proc. Zool. Soc., 1876 ; Pander, Die Ctenodipterinen des Devonischen Sys- 

 tems, 1858 ; Traquair, On the Genus Dipterus, &c., Ann. and Mag. Nat. 

 Hist., 1878.) 



