Hector. — On the Dolphins of the New Zealand Seas. 207 



poisoned. It descends into Wellington during hard weather, and if the 

 Empire City is not spared, we must look for a like visitation from time to 

 time. 



Some say that the colour of our rat is not dark enough to admit of the 

 opinion that it is a " Kiore Maori." But the Mus rattus. is said by a dis- 

 tinguished naturalist to change from black to grey — very old individuals 

 becoming decidedly hoary (Trans., vol. iv., p. 184). We should hesitate, 

 therefore, before pronouncing positively as to the classification of a rat from 

 coloiir alone. Anatomical structure, size, and habits seem to be more im- 

 portant elements to consider. 



3. As to what it is that causes the death of so many of our visitors — 

 for their corpses in various stages of decomposition lie about our properties 

 everywhere — there need be no difficulty. Their enemies are numerous. 

 Every man's hand is against them. Dogs and cats worry them about our 

 houses. Native birds pounce upon them in the open fields. Their more 

 powerful congeners — the brown rats — wage war against them a outrance. 

 A survey party in Motueka the other day dug out a rat hole, and found 

 therein a Norwegian female and her young, and by their side about twenty 

 skins and other remains of the smaller rat. Besides these enemies they 

 have to contend with disease, probably occasioned by change of food and 

 surroundings. Moreover, they do not seem to have the experience or 

 cunning of the brown rat as to the avoidance of danger ; and as their 

 numbers are so great, their slaughter is proportionately wholesale. Between 

 them and the brown rats there will of course be a war of races. But the 

 black rat, neither in Europe nor here, has ever been a match for the other 

 rodent. We shall not have these interesting strangers amongst us long — 

 already they are diminishing in numbers, and soon they will probably retire 

 to their mountain fastnesses as mysteriously as they descended upon us. 

 If we did not welcome their coming, I think without doubt we shall speed 

 the parting guests. 



Art. XXIII. — Notes on the Dolphins of the New Zealand Seas. 

 By James Hector, C.M.G., M.D., F.E.S. 



[Read before the Wellington Philosophical Society, 26th November, 1884.] 

 In 1872* I collected all the information at my command respecting the 

 dolphins that frequent our coasts, and distinguished the species according 

 to the mode of classification adopted by the late Dr. Gray in his catalogue. 



* Trans. N.Z, Inst., vol. v., art. xix. 



