74 



CETACEA. 



seen well developed in the skeleton of the gigantic Ostend "Whale, 

 which was formerly exhibited at Charing Cross and in other places. 

 This peculiarity is found both in the Eight Whales and in the 

 FinnerSi 



Indeed, when the skeletons of the specimens from different loca- 

 lities can be examined, there are no want of characters to separate 

 the Whales into genera and species ; as, for example, the breadth 

 of the upper jaw, the size and form of the ramus of the lower jaw, 

 the form of the lateral processes of the cervical vertebrae, the number 

 of the dorsal and caudal vertebrae, the form and size of the articu- 

 lating surfaces of the vertebrse, the form and number of the ribs, the 

 form of the os hyoides and of the sternum, the shape of the scapula 

 and the development or non- development of the coracoid process, the 

 form and proportions of the bones of the arm, and the number and 

 comparative length of the bones of the paddle. I am convinced that, 

 when more skeletons have been collected, the number of the species 

 of these animals will be greatly increased, especially if the bones of 

 the skeletons are kept separate, and not set up, so that the bones of 

 the different species can be accurately compared. For it is to be 

 observed, probably from the eye not being able to take in the pecu- 

 liarities of so large a subject, that some of the best comparative 

 anatomists, as Eschricht and Van Beneden, have regarded skeletons 

 from very different localities, as the Megwpterce from the Northern 

 Seas and from the Cape, as the same species, from a comparison of 

 set-up skeletons, which were at once declared to be distinct when 

 the separate bones were compared in detail. 



Mr. Flower, in his excellent paper " On the Skeletons of Whales 

 in the principal Museums of Holland and Belgium " (Proc. Zool. Soc. 

 1864, 384), observes that in studying and describing Whales or their 

 skeletons it is most important to ascertain the age of the specimen. 



The animals may be divided by their skeletons " into three periodsi 

 of growth." 



1. In the first, all the epiphyses of the vertebral column and of 

 both ends of the humerus, raius, and ulna are still separate, and 

 the processes of the vertebrae axe very incomplete. The animal 

 remains in this condition until it has attained to more than half the 

 length of the adult. This stage of growth may be designated as 

 " young." Towards its close the majority of the bones lose the spongy 

 character of the " very young " animal, and acquire the form and 

 structure characteristic of succeeding ages. 



2. In the next stage, both epiphyses of the humerus, those of the 

 upper end of the radius and ulna, and those of the bodies of the 

 anterior cervical and the anterior caudal vertebrse are imited, while 

 those of the greater part of the column are still free. The ossifica- 

 tion of the transverse processes of the cervical vertebrae, although 

 often still incomplete at the ends, has gone on so far as to give them 

 in great measure the characteristic form seen in the adult. This is 

 a condition in which skeletons are frequently seen in museums. The 

 animal in this stage, which may be caUed " adolescent," has attained 

 nearly its full size. 



