48 



addition to the seven cervical ones; but these cervical vertebrae 

 are all so confluent and soldered together, as it were, into one 

 bone, that it is more difficult to distinguish them from each 

 other than perhaps in any other cetacean, although the soldering 

 of all the seven cervical vertebrae into one piece occurs not 

 unfrequently among the dolphins. 



In this sublunary creation, every organic structure passes oif 

 gradually to some other one ; and it is in consequence of this 

 law of nature that almost all characters, however distinctive of 

 groups they may appear on a first glance, will be found to 

 give way at some point or other of any series which forms a 

 group. Few characters, for instance, can more generally 

 denote the class of Mammalia than their seven cervical verte- 

 brae. The atlas, the axis, and the five others are all to be 

 seen distinct in the dolphin of the Ganges, as well as in the 

 swan-like neck of the cameleopard. Among the sloths 

 however, we find one species with nine cervical vertebrae, 

 and on the other hand among Cetacea we often see their 

 seven cervical vertebrae soldered together into one. The 

 sperm whale, or Catodon, as we have seen, has its atlas 

 distinct, but its axis and the following five vertebrae are 

 soldered together into one piece. When a character of this 

 kind breaks down, it becomes, from its tendency to vary, of 

 little more value than to distinguish species. Thus Del- 

 phinus delphis^ D. globiceps, D. griseus, and Phoccena coin- 

 munis, as also the genus Hyperoodon, have all the cervical 

 vertebrae soldered together. Delphinus Tursio has them all 

 distinct, as well as the Platanista or Delphinus Gangeticus, 

 Linn. In the Cape Rorqual the atlas is distinct, and also the 

 four last vertebrae, but according to Cuvier the axis and the 

 third joint are soldered together. In the Cape whale the 

 whole seven are confluent into one piece. 



In the Eiqyhysetes Grayii the one bone, which is formed of 

 the seven cervical vertebrae, has the atlas and axis marked out 

 in it by their superior blunt conical transverse apophyses, as 

 in the Cape whale ; their inferior apophyses being evanescent 

 as in dolphins. The third and fourth vertebrae are thick. 



