PSEUDORCA CRASSIDENS. 205 



Kiel specimen, ten dorsal vertebrae may certainly be considered to be the normal number in this 

 species, which, accordingly in this manner, will be provided with seven cervical, ten dorsal, ten 

 lumbar, and lastly, twenty-three caudal vertebræ. In consequence of this comparatively small 

 number of the vertebræ, the single vertebræ, especially in the hindmost part of the dorsal region, 

 in the lumbar region, and the greater part of the tail, are more extended in length than in the 

 ca'ing- whales and the killers, and as moreover the spinous processes are somewhat lower than is 

 the case, not only with the former, but also with the latter, the appearance of the spine, generally 

 speaking, will be found to differ not a little from that of the spine of an Orca, and still 

 more from that of the spine of a ca'ing-whale. It may further be inferred that our 

 species is in this respect no less different from the DelpMnus griseus also, both from 

 the considerable difference between these two animals in the number of their vertebræ, and 

 from Cuvier's words about this species, first described by him : " Les apophyses epineuses s'elevent 

 beaucoup sur le commencement des lombes," seeming also to denote that such is the case ; but 

 his description is so short, that we are not able from it alone to obtain an accurate idea of the 

 peculiarities of the spine of this DelpJiinus griseus} 



If we pass to the examination of the details of the vertebral column, and in the first place to 

 that of the cervical vertebræ, we shall find that the ankylosis of these is farther advanced than 

 either in the killers, or in the ca'ing- whales. For though in old animals of the former species, the 

 four or five, or in rare instances,"perhaps, even the six foremost cervical vertebræ may be ankylosed 

 by means of their spinous processes/ yet it is only the two, or, at most, the three foremost 

 of the vertebral bodies that are ankylosed ; the rest of them always remain separate, and though 

 the bodies of the six foremost cervical vertebræ may sometimes be ankylosed in the ca'ing-whales, 

 yet both the sixth and the fifth may also, even in very large, and evidently very old individuals 

 remain separate from each other, and from the preceding ones. But in the species of 

 which we are now treating it is not only the six foremost, but in some individuals, even all seven 

 cervical vertebræ that have their vertebral bodies ankylosed. Thus, the former is the case in the 

 individual drifted ashore a,t Asnæs, the latter in the male stranded at Middelfart ; it is true, that 

 only the five foremost cervical veretebræ have their bodies ankylosed^ in the individual found at 

 Refsnæs ; but this must most probably only be considered as a consequence of the greater youth 

 of this individual ; for the thin posterior epiphysis of the fifth cervical vertebra is not united 

 with the middle piece of the vertebral body, and both the epiphyses of the sixth are still free ; 

 and it is certainly probable that, just as the anterior osseous disk of the fifth vertebral body is 

 already perfectly united, not only with the middle piece of the body, but further with the body 



^ 'Kech. s. 1., Oss. Foss.,' 4me ed., torn. 8, 2, page 147. 



^ Of the cervical vertebræ of an Orca from the Skagerak preserved in the Royal Museum, the 

 four foremost are perfectly ankylosed by means of their spines ; the spine of the fifth cervical vertebra 

 is, indeed, perfectly separated from these ankylosed spines of the preceding vertebræ, but, on the other 

 hand, it is again ankylosed to the spine of the sixth cervical vertebra, and it is placed so closely up to 

 the fourth one, and the irregularities in the contiguous surfaces fit so exactly together, that the thought 

 strikes us quite naturally that these, too, are going to be ankylosed, and that if the animal had grown 

 somewhat older, all the six foremost cervical vertebræ Avould have been united by their spinous 

 processes, while only the three foremost are ankylosed also by their bodies. 



^ The same was the case with the individual on which Owen founded his Phocæna crassidens, 

 but we are not informed whether this was a young animal or not. 



