3IO MAMMALIA. 



Order CETACEA. 



Marine rarely fluviatile Mammals, with a thick, hairless skin and a 

 flattened caudal fin ; a certain number of the seven cervical vertebrae 

 confluent ; no sacrum ; only very few of the ribs are provided with a 

 capitulum or are connected with the sternum ; no clavicles ; the 

 forelimbs are not provided with nails and form broad flattened 

 paddles ; the traces of the hind limb are scanty and entirely inter- 

 nal ; the brain case is spheroidal, with broad basis cranii ; the fused 

 supraoccipitals and interparietals generally meet the frontals in 

 front and separate the small laterally placed parietals from one 

 another ; a large supraorbital present ; nasal bones very short, not 

 covering the ventral nasal passages ; rami of mandible with no 

 ascending process ; dentition homodont, monophyodont, teeth with 

 single roots; pinna auris absent ; stomach complex ; saHvary glands 

 absent; kidneys lobulate; os penis not present; mammae inguinal 

 two in number ; placenta diffuse. 



Our knowledge of the Indian Cetacea is primarily due to Blyth, 

 who wrote a paper in the Journal of the Asiatic Society, Vol. 

 XXVIII, describing all the remains of Cetacea from Indian seas 

 which he had been able to secure for the Museum of the Asiatic 

 Society ; secondly, to Anderson, who in his Anatomical and Zoolo- 

 gical Researches, gives a complete account of the two fresh-water 

 Dolphins of Indian Rivers, and of the skeleton of the fin-back whale 

 found in the Indian Ocean ; and, lastly, to Owen, who (Trans. Zool. 

 Soc, Vol. VI) described the remains of a large number of Indian 

 Cetacea collected by Sir W. Elliot on the Madras Coast. 



The following synopsis is entirely based on the various writings of 

 Prof. Flower, of which the chief are the papers in the Transactions 

 of the Zoological Society, Vol. VI, in the Proceedings for 1883, and 

 the articles Mammalia and Whales in the Encyclopaedia Britannica. 



Synopsis of Indian Genera, 



a. Teeth never functionally developed ; upper jaws provided with 

 plates of baleen ; external respiratory aperture double ; rami 

 of mandible arched outwards, the anterior ends connected by 

 fibrous tissue only ; sternum a single piece connected with one 

 pair of ribs only [ =Mystacoceti]. Balenoptera, p. 313. 



a^. Teeth present and functional ; no baleen ; external respiratory 

 aperture single ; rami of the mandible straight, the anterior 

 ends forming a true symphysis ; sternum of several pieces and 

 connected with several pairs of ribs. [ =Odontoceti.] 



h. Costal cartilages not ossified ; hinder ribs loose the tubercular 

 and retain the capitular articulation with the vertebrae; 



