64 BELPHINIDJ!. 



1. Inia GeoflEroyii. 



Inia Geoflfroyii, Gray, I. c. pp. 226, 393 ; Synops. Whales ^ Dolph. 



p. 4; Flower, Trans. Zool. Sob. vi. p. 87, t. 25, 26, 27 (skeleton). 

 Delphinus amazonicua, Spix, Reise in BrasU. t, iii. pp. 1119 and 1113, 



fig. 34Cbad). .... * 



Inia Qeofirensis, J)' Orhigny, in Ann. Mus. Paris, vol. iii. p. 23 ; Ger- 



vais, OsUog. C4t. t. xxxii. 



Inhab. Brazil, river Amazon. 



" The number of the teeth in the dififerent specimens of Inia exa- 

 mined shows a considerable range of variation, presuming that they 

 all belong to one species. In the one now described there are 

 B 25'l 27 ~^^^' ^^® larger specimen in the British Museum, 

 from Ega, has °^^° =109, and also two minute rudimentary teeth 

 in the gum behind the last in the left maxilla. In the smaller skull 

 from the same place there are 2^^=110. In the skull in the 

 Paris Museum, brought by D'Orbigny, there are, according to Ger- 

 vais, |^^j=132; but in the type specimen in the same museum, 

 taken from Lisbon, the number is given by De Bainville as 

 ^^=104. In the BerUn skuU the teeth are 3-^2=131. Von 

 Martius, in his diagnosis of the species, gives |^?=114." — Flower. 



Fanuly 10. DELPHINID^, 



Delphinidse, Gray, I. c. pp. 228, 393 ; Synops. Whales Sr Dolph. p. 4 ; 

 FUmer, Trans'. Zool. Soc. vi. p. 113. 



Head beaked. Teeth in both jaws, conical or compressed, per- 

 manent, without any internal lobe, occupying nearly the whole 

 length of the jaws. Back rounded, with a falcate dorsal fin ; rarely 

 absent. SkuU with the maxilla expanded over the orbit, and more 

 or less turned up on the edges. 



" Costal cartilages firmly ossified. Posterior ribs losing their capi- 

 tular articulation, and only uniting with the transverse processes of 

 the vertebrae by the tubercle. Anterior (2-6) cervical, in most, an- 

 kylosed together. Pterygoid bones short, thin, involuted to form, 

 with a process of the palatine bone, the outer wall of the postpala- 

 tine air-sinus. Numerous teeth in both jaws (Monodon excepted), 

 sometimes deciduous. Symphysis of mandible short or moderate, 

 never exceeding one-third the length of the ramus. Bones of the 

 skull not raised into a distinct crest behind the anterior nares. 

 Orbit of moderate size. Lachrymal bones not distinct from the 

 jugal. Pectoral limbs varying much in form and size. Dorsal fin 

 usually present." — Flower, 



