446 Transactions.— Zoology. 
lation with the skull, and have afterwards for some distance still a roundish 
form, then gradually flattening, till, about 2-5 inches from their anterior 
end, they are 1-71 inches broad and 0°5 inch thick, the upper side having 
a sharp ridge and the lower side being flattened. 
Vertebral Column. 
The number of vertebrz is as follows :— 
ervical T 
Thoracic 10 
Lumbar 10 
Caudal 19 
46 
Mesoplodon floweri thus agreeing in that respect with Mesoplodon sowerbiensis. 
Cervical Vertebra. 
Measured along the lower side of their main bodies, the seven cervical 
vertebre have a total length of 5:75 inches. 
Of these the atlas, second and third vertebre, are united to one large 
triangular bone, 8 inches broad and 6-10 inches high. Only their lower 
proeesses, of which those of the second are the largest, are free. 
The third vertebre has two distinct transverse processes, on each side of 
which the higher one (diapophysis) is a thin bone with its termination point- 
ing downwards. The next four vertebre are all free, and if we take into 
consideration that the skeleton under review belonged to a fully adult 
animal, there is no doubt that no further change in their relation to each 
other would have taken place. 
The upper as well as the inferior transverse processes become gradually 
smaller as we advance towards the thoracic region. In the fourth vertebra 
the inferior transverse process has still a horizontal direction. In the fifth 
it assumes a downward slope, which is continued to the seventh, where it 
consists only of a small tubercle. Above it on the side of the body of this 
vertebra is the articular surface for the head of the first rib. The fourth 
vertebra had evidently a small spinous process, which doubtless was broken 
offin cleaning it. In the fifth the spinous process is 1*05 inches ; in the 
sixth, 1:53 inches; and in the seventh, 2 inches high, all leaning a little 
forwards. 
The bodies of the four last vertebre are broader than they are high. 
Mesoplodon floweri therefore stands so far alone in regard to the arrange- 
ment of the cervical vertebre ; as no other Ziphioid Whale, as far as I am 
aware, las the three first cervical vertebrae anchylosed and each of the next 
four perfectly free. 
