242 



Transactiuas. — Zoology, 



the cheeks, where blackish blotches advance some distance towards the nose. 

 The cylindiical form of the animal for its length is rather slender, its height 

 at the occiput being only 2 feet 3 inches, and at about nine feet from the tip 

 of the lower jaw 3 feet 3 inches, after which it tapers gradually to the tail. 

 The animal proved to be a young female, 



The two teeth at the termination of the lower jaw stood half an inch 

 above the gums, having a diameter of one inch where they rose above the 

 latter. They are conical, and have a sharp apex, and are not covered any- 

 where with enamel, not even on the tip. The dentine shows a number of 

 horizontal lines one above the other, running round the tooth. They are 

 therefore quite different from the teeth of the two specimens described in 

 Vol. IX. (Transactions of the New Zealand Institute), which were found to 

 be covered with a rough cement. They are also different from those of 

 another specimen, of which I shall give some details further on. 



A single fold begins- below the throat, 1 foot 1 inch fi'om the top of the 

 lower jaw. After rising rapidly for four inches, it continues for seven inches 

 more at a smaller angle, ceasing where the black colour of the throat begins. 

 This fold is separated into two portions by a ridge of the breadth of half an 

 inch below the centre of the throat. 



Lips flesh-coloured ; roof of mouth slaty-black ; no signs of teeth along 

 the jaws ; there is, however, a hardened ridge along both sides of the palate. 

 The extremity of the lower jaw projects about two inches beyond the upper. 

 The head rises steeply above the upper lip to the forehead. 



The blow-hole is situated on the vertex of the head just above the eye. 

 Both the form and the size of the dorsal fin and of the tail-lobes, show that 

 this species must be a remarkably swift swimmer. 



Measurements. 



Total length 



Greatest circumference 



From point of lower jaw to the beginning of the pectoral fin 



From fork of tail to termination of falcate dorsal fin 



Length of the opening of the mouth 



From point of lower jaw to eye 



From point of lower jaw to beginning of fold below throat 



Diameter of blow-hole concave towards head 



From fork of tail to vent 



From fork of tail to pudendum 



Breadth of caudal fin 



Base of dorsal fin 



Height of dorsal fin 



Breadth of pectoral fin 



Length of pectoral fin 



Eye, horizontal diameter 



Eye, vertical diameter . . 



FT. 

 . 19 



IN. 



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