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CHAPTER XXX. 



CETACEA WHALES AND DOLPHINS ZEUGLODOX PLATANISTA. 



The few points of analogy which can be specially traced between the Whales and other orders 

 of mammals are chiefly with the Pachyderms ; and most of these are rather points of analogy or 

 resemblance than of affinity. Their size is the greatest argument for their relationship, and most of 

 the other coincidences are probably only a necessary consequence of the size, as that the transverse 

 diameter of the encephalon exceeds the longitudinal, a proportion observed onlj- in Cetaceans and 

 Proboscideans. There are others which have no apparent connexion with the necessities of the 

 structure, but are more indicative of nature having been working in the same groove, as if the 

 idea which had been already used in the one animal, again occurred to be used in a difi'erent form 

 in the other. The whale-bone of the Baljena, for example, may be said to bo the same idea, differently 

 expressed, as the hornj' plates in the mouth of the Ehytixa, which we have just left ; or the 

 long tusks of the Narwhal, may be homologous to the tusks of the Elephant, both growing from a 

 permanent pulp (an organisation, however, shared by the Rodents), or their usual monodont develop- 

 ment to a similar heterodox arrangement which seems to have been common in the under tusks of the 

 Mastodon. 



The dentition of the Cetacea, however (and a more Important part of its structure cannot 

 be cited), differs so greatly from that of the Pachyderms, that only the most distant relationship 

 can be surmised. When we inquired into the probable derivation of the Seals, we had some 

 faint light to guide us, because they undoubtedly belonged to the Carnivora ; but we are without 

 any such giude-posts here ; although the Cetacea are carnivorous, as well as the Seals, their structure 

 is so different, that they cannot be ranged under the same category as them, any more than along 

 with the Pachyderms. They stand apart a peculiar order. No discovery of extinct animals has 

 ever thrown any additional light upon it. ■^^^len a new animal, as the Zeuglodon, turns up, it 

 has always fitted readily to a place in one or other of the already recognised sections of the order. 



Their first appearance seems to have been at the later eocene, or earlier miocene. There is, 

 indeed, a statement that, like one of the Seals, remains of a AVhale had been found in North 

 America, in the greensand of New Jersej', which corresponds to our strata below the chalk. 



Their supposed existence in the greensand rests upon the rather slender basis of two question- 

 able vertebrae. These were described by Dr. Lcidy* of Philadelphia, as belonging to two species 

 of a new genus of Cetaceans, which he named Priscodelphinus. Sir Charles Lyell saw these in 

 1853, and afterwards traced one of them to a Miocene marl pit in Cumberland County, New Jersey ; 

 consequently it was put out of court. The other, which had been mistaken for a bone of the 



* " ProcoodinofS of Aca.l. Nat. Sc. Philarl.," 1851. 



