Hector. — New Zealand Cetaceans. 



161 



to base of dorsal ; a single dorsal, low and ronnded, commences at middle of 

 back and over the umbilicus. Tail-lobes narrow, falcate, each one-third longer 

 than the pectoral. 



l!Tose and forehead pure white, bounded by a crescent of black behind the 

 blow-hole, sharply defined in front, but shading off behind to light grey, 

 which is the uniform colour of the upper surface of the body. Fins are all 

 darker than the trunk ; there is also pure black round the blow-hole, cloaca, 

 and vent. The white of the snout extends behind the eye, but the dusky 

 colour extends forward beneath the angle of the mouth. The lower aspect is 

 white as far back as the vent, but is crossed by an isthmus of dark grey 

 beneath the pectorals. The white band is continued by two lateral stripes 

 that ascend on the flanks. The colouring, as far as I have been able to judge 

 by casual inspection is very uniform in all the individuals. 



This dolphin differs in external characters from the genus Lagenorhynchus 

 (as described in the " Catalogue of Seals and Whales," p. 267) in the 

 forward position of the dorsal, and the absence of a second fin-lobe on the 

 back. 



Common in Cook Strait, and on the West Coast as far south as Jackson 

 Bay, travelling in large schools. 



A Bottle-nose shot in 1871 had a total length of 51 inches, girth 32 



inches, and weight 78 lbs. 



Dimensions. 



Inches. 

 Snout to anterior margin of pectoral ... ... ... 12 



,, angle of mouth ... ... ... ... 6 



,, blow-hole ... ... ... ... ... 8 



„ commencement of dorsal ... ... ... 24 



,, umbilicus ... ... ... ... ... 24 



5, vent ... ... ... ... ... 36 



Length of base of dorsal ... ... ... ... 8 



Spread of tail ... ... ... ... ... 15 



Length of anterior margin of tail-lobe ... ... ... 12 



There is a complete skeleton and several skulls and lower jaws in the 



Colonial Museum, this being the most commonly cast up of any of the 



dolphins round the coast. 



The skull is flask-shaped, the beak being wide at the base, rapidly tapering 



to an acute point in front, with the edges bevelled in a regular manner. The 



teeth are small, cylindrical, curved, and pointed. Palate slightly conca.ve. 



The length of the adult skull is 14 inches, the beak forming half the 



length, and being three times the width of its middle part ; height of the 



occiput 5*7 inches. The cervical vertebrae are anchylosed into a solid mass 



1'3 inch in length. 



