226 INIIDiB. 



B. Nostrils united into a single transverse or crescent-shaped blower. Head 

 moderate, more or less beaked. Teeth in both Jaws, often deciduous. 

 I%e pectoral Jin lanceolate, tapering. 



Family 5. INIIDiE. 



The head beaked; beak bristly. Teeth in both jaws, conical, 

 rugulose, crown of the hinder ones with an internal process. Back 

 without any fin, keeled behind. Pectoral fin large, lanceolate. 

 Skull : maxillary bones simple, expanded over the orbits. Jaws 

 compressed. Symphysis of the lower jaw elongate. FluviatUe. 



Iniadas, Gray, Proc. Zool. Soc. 1863, May. 



Delphinidae Iniana, Orav, Zool. Erebus fy Terror, 45 : Cat. Cet. B. M. 

 1850, 60, 135. 



1. INIA. 



Head rounded, convex. Nose produced, nearly cylindrical, taper- 

 ing, hairy. Blowers oblique, nearly above the pectoral fin. Ear- 

 hole distinct. Teeth numerous, rugose, grooved, permanent ; the 

 front hooked ; the hinder, close at the base, with a large rounded 

 tubercle on the inner side. Dorsal fin none, but the back is keeled, 

 ovate, and subtriangular behind. Body compressed behind. Pec- 

 toral fin large. The skull depressed, with the nose twice as long as 

 the brain-cavity, compressed, with a groove along each side. Tem- 

 poral cavity very large, edged above by a strong crest ; the orbital 

 hole very short, roundish. Muzzle of the young hairy. 



Inia, jyOrbigny, Ann. Sci. Nat. ; Nonm. Ann. du Mus. viii. Ill, 1834 j 



Institute, 1834, 246. 

 Delphinus, sp., JDesm. 

 Delphinorhynchus, sp., F. Cuvier. 



1. Inia Geoffroyii. The Inia. 

 Pale blue, reddish beneath ; fins and tail oUve. Some reddish, 

 others blacker. Teeth fl— |f. 



Delphinus Geofiroyii, Desm. Mamm. 612. 



Delphinus Geoffroyensis, Blainv. ; Desm. N. Diet. H. N. ix. 151 ; 



Gervais, Castebiau, Voy. Mamm. 89 ; . Comptes Sendus, 1856, 806 ; 



Ann. Nat. Hist. xvii. 521 ; Arch. Naturg. 1857, 27 ; Gray, Ann. ^ 



Mag. N. H. 1856, xviii. 157. 

 " Delphinus a bee mince," Cuvier, M. A. i. 278 ? 

 Delphinorhynchus frontatus^ F. Cuv. CUac. 121. 

 Delphinorhynchus Geofiroyii, Lesson, Man. 405. 

 Delphinus Inia, Sehlegel, Abhandl. 24, 

 Delphinus Amazonicus, Martius, H. Schomburgk, Meisen in Brit. 



Guiana, iii. 786. 

 Inia Boliviensis, D''Orbigny, N. Ann. Mus. iii. t. 22. f. 3, cop. F. Cm. 



CUac. 166. t. 10*, t. 11; Geru. in D'Orb. Voy. Am^. M6rid. 60. 



t. 22 (animal and skull); Gray, Ann. fr Mag. N. H. 1866, xviii. 157; 



'Gervais, Ann. Sf Mag. N. H. 1856, xviii. 52 ; Institute, 1856, 806. 

 Bufieo der Missionaires, Castelnau, Hist, du Voy. dans VAm4r. du Sud, 



iv. 469; Arch. Naturg. 1853, 24. 



