REPORT ON THE CETACEA. 23 



brarterial foramen." The inferior transverse processes of the more anterior vertebrae were 

 almost horizontal, but the more posterior had this process sloping downwards and out- 

 wards, and but slightly projecting ; in the seventh it was reduced to a mere tubercle. On 

 each side of the body of the seventh vertebra was a distinct articular surface for the 

 head of the first rib (PI. I. fig. 3). 



In the union of the anterior three vertebras into a single bone, this specimen agrees 

 with the Mesoplodon layardi described by Dr von Haast, and it differs from Mesoplodon 

 grayi and Mesoplodon australis described by Professor Flower, and from Mesopilodon 

 soiverbyi, in all of which only the atlas and axis are fused together. It may be^ taken, 

 therefore, as a piece of evidence, which is of value as far as it goes, in favour of the 

 opinion expressed in this Eeport, that Dr von Haast's specimen from Saltwater Creek 

 is of the same species as this one from the Falkland Islands. 



In the dorsal vertebrce the bodies increased in size from before backwards. The first 

 had a pair of slight tubercles projecting from its inferior surface in series with, but 

 smaller than, the inferior transverse processes of the seventh cervical vertebra. A mesial 

 ridge appeared on the inferior surface of the body of the sixth dorsal, which was more 

 strongly marked in the hinder members of the series. In all, the laminae and spines were 

 complete, and became more massive from before backwards. The spine of the first, 

 comparatively slender, was directed slightly forwards, that of the second was almost 

 vertical, whilst those situated behind the second inclined a little backwards. Articular 

 surfaces for the heads of the second, third, fourth, fifth, and sixth ribs were very distinct 

 on the posterior border of the side of the bodies of the anterior five dorsal vertebrse, 

 situated close to the place of origin of the pedicle. In the second, third, fourth, and fifth 

 vertebrae a larger proportion of this articular surface was on the pedicle than on the body 

 as compared with the first and sixth dorsal vertebrae. The articular surface for the 

 head of the seventh rib was partly on the posterior border of the side of the body of 

 the sixth, and partly on the anterior border of the seventh vertebra, its articulation with 

 the seventh being better marked on the right than on the left side. The articular surface 

 on the anterior part of the side of the body of the seventh vertebra was on a slightly 

 projecting process, which was in series and obviously homologous with the much more 

 strongly projecting processes from the side of the bodies of the eighth and ninth dorsal 

 verteljrae. The anterior seven dorsal vertebrae had each a pair of broad transverse 

 processes springing from the pedicles, close to the anterior articular processes, for arti- 

 culation with the tubercles of the anterior seven pairs of ribs. These transverse processes 

 projected forwards and somewhat downwards in the more anterior dorsal vertebrae, but 

 in the sixth and seventh outwards and downwards. The long axis of the articular sm'face 

 for the tubercle of the rib also changed in its direction, for on the transverse processes 

 of the first and second it was almost vertical, further back it became oblic^ue, but on 

 the seventh dorsal it was horizontal and antero-posterior. The long axis of these articular 



