Dolphins of the New-Zealand Seas. Ill 



Ifinger and more attenuated lower jaw, and much slenderer 

 teeth, than the Chatham-Island specimen, figured and described 

 1 )y Dr. Hector under that name ; and I have very little doubt 

 in my own mind that the Chatham-Island specimen will be 

 found, when more perfect specimens are obtained, to be the 

 representative of a very distinct species of Dolichodon, which 

 I would propose provisionally to designate as Dolichodon Tra- 

 TPrsii — a curious comment on the comparative anatomists, who 

 tliink that Dolichodon Layardi of the Cape, Callidon GUntheri 

 of New South Wales, Petrorhynchus capensis of the Cape, &c. 

 '' all differ in so trifling a degree as not to exceed the range of 

 individual variations one often meets with in comparing a series 

 of skulls of the same species," Surely the author means 

 of the same domestic animals, and entirely leaves out of the 

 question the experience gained by the study of wild ones and 

 the evidence afforded by the study of their geographical distri- 

 bution. 



I must think that when these authors become more expe- 

 rienced they will wish their observations to have a "tacit 

 burial and oblivion," and perhaps themselves learn how to 

 define genera and species. 



15. Berardius Hectori. 

 I know nothing of this skull except from Dr. Hector's 

 figures and description: and the skull has never been in England; 

 so that I do not think that any comparative anatomist has had 

 the opportunity of seeing it. Dr. Hector considered it the 

 young of B. Arnouxi. I at once saw that it was different ; but 

 as it has the teeth in the front of the jaw like Berardius^ I 

 considered it best {and am still of the same opinion) to retain 

 it in that genus, with which it agrees in the position of its 

 teeth as developed in the adult animal, and in geographical 

 distribution ; and Dr. Hector's tracings of the ear-bones of the 

 two species show that there is a great affinity between them in 

 the verypeculiar manner in which those bones are dotted. I con- 

 sider the position of the teeth a more important zoological cha- 

 racter than a slight difference in the " conformation of the naso- 

 premaxillaiy region," a part that, as every zoologist who has 

 examined several skulls of different ages in the same species 

 of Cetacea knows, is very apt to vary ; but when a comparative 

 anatomist draws his conclusions from figures, or the examination 

 of a single specimen of a group, he is often liable to be misled 

 as to the value of the characters to which he attaches much 

 importance. Nothing showed this better than the published 

 results of the labours of a comparative anatomist who has 

 named, but not defined, a multitude of species and genera from 



