TNIID^. 63 



I. Pectoral fin elongate, obliquely truncated on the timer side. Fingers elon- 

 gate, longer than the arm-bones, unequal; the second and third much 

 the longest ; the rest short. Forearm-bones close, together, only sepa- 

 rated by a straight line. Carpal bones moderate, 5 or 7 (cf. p. 85). 



A. Pectoral Jin on the side of the body. Second and third I fingers of six or 

 eight phalanges (cf. p. 82). 



Family 9. INIIDiE. 



Iniidae, Gray, I. c. pp. 02, 22G ; Synops. Whales 8f Dolph. p. 4. 

 Platanistidfe (Iniinas), Flower, Trans. Zool. Soc. vol. vi. p. 114. 



Fluviatile. Head beaked ; beak bristly. Teetb in the jaws, ru- 

 gulose, crowns with an internal lobe ; permanent. Pectoral fin 

 large, elongate, subfalcate. Back keeled behind, without any dorsal 

 fin. Skull — jaw compressed ; symphysis of lower jaw elongate, ex- 

 tending for more than half its length. Overlooking the form of the 

 blower, Mr. Flower places this genus with Platanistidas. 



Vertebras 41. C. 7. D. 13. L. 3. C. 18. The smaUest num- 

 ber of any Cetacean known. 



" Costal cartilages not ossified. The tubercular and capitular ar- 

 ticulations of the ribs blending together posteriorly. Cervical ver- 

 tebras all free. Pterygoid bones thin, not conforming in their mode 

 of arrangement with either of the other sections. Jaws very long 

 and narrow, both with numerous teeth having compressed fangs. 

 Symphysis of mandible very long, exceeding half the length of the 

 entire ramus. Orbit very small. Lachrymal bones not distinct 

 from the jugal. Pectoral limbs large. Dorsal fin rudimentary." 

 — Flower. 



" Maxillary crests absent, or very slightly developed. Many of 

 the teeth with a complete cingulum or a distinct tubercle at the 

 base of the crown. Pectoral fin ovate, obtusely pointed." — Flower. 



1. INIA. 



Inia, Gray, I. c. p. 226 ; Synops. Whales <§• Dolph. p. 4 ; Flower, Trans. 

 Zool. Soc. vi. p. 87. 



Cervical vertebras free : the first with an inferior posterior pro- 

 cess, bifid at the end ; lateral processes very short : the second 

 with a strong dorsal process. Dorsal vertebrae with very high dorsal 

 processes. Scapula very high, with very long acromion and cora- 

 coid processes. The arm-bone short. Forearms thick and short, 

 scarcely so long as the upper arm-bone. Metacarpal bones seven, 

 imbedded in cartilage. The second and third fingers very long, with 

 six phalanges ; the first finger very short, of two phalanges ; the 

 fourth strong, short, about as long as the first two phalanges of the 

 third finger, of four phalanges ; the fifth finger very short, slender, 

 of three phalanges. The breast-bone ovate, scutate, notched in 

 front. 



