282 WHALES AND DOLPHINS 



jaw distinguish this species, about whose external appearance 

 nothing whatsoever is known. 



In Mesoplodon minis, True's Beaked Whale, the teeth are 

 inserted in sockets at the very tip of the lower jaw and project 

 obliquely forward. They are easily distinguishable from those 

 of Cuvier's Whale, with which this species might be confused, 

 by being pronouncedly compressed laterally. The original 

 specimen described by True in 1913 had the following body 

 colouring : " back, slate black ; lower sides, yellow purple, 

 flecked with black ; medium line of belly somewhat darker ; 

 a greyish area in front of the vent ; fins the colour of the back." 

 It was an adult female 16 feet long, and the two teeth entirely 

 concealed beneath the gum were slender in form. In a male 

 specimen 17 feet long, stranded on the coast of co. Clare, 

 the teeth were much more massive than in the female just 

 mentioned. They projected nearly an inch beyond the tooth 

 sockets, and in the living animal the tips were probably exposed 

 above the tissues of the gums. The flattened oval cross-section 

 of the tooth was 1 inch by slightly more than | inch. 



The five known specimens were found — one each on the 

 coasts of North Carolina and New England, two on the coast 

 of Ireland, and one on the Outer Hebrides. 



The species of the genus Mesoplodon are difficult to describe 

 by external characters alone, and the group is one about 

 which much is still to be discovered. The reduction in the 

 number of teeth, and the extreme modification of the functional 

 pair that persist, contribute to the interest of a genus which 

 must be considered extraordinary even in the highly specialized 

 group of mammals that constitutes the Order Cetacea. 



Genus Tasmacetus. 



A new genus and species of Beaked Whale, Tasmacetus 

 shepherdi described by Dr. W. R. B. Oliver, New Zealand, is 

 distinguished from all other Ziphioids notably by having a 

 series of 19 functional teeth in each upper jaw row, besides 

 26 teeth of comparable size in each lower jaw and a pair of 

 larger bulbous teeth at the tip. A newspaper reported the head 

 as distinctly bulbous, eye fairly large, skin black on the back 

 striped with greyish yellow on the sides and white underneath. 

 It is known only from New Zealand. 



