208 



Transactions, — Zoology. 



In 1876, when describing the osteology of Tursio metis, I pointed out the 

 importance of the palatal aspect as affording a ready means of distinguish- 

 ing the skulls of our dolphins, and gave figures of this aspect for the five 

 species of most frequent occurrence.* So far as I know, no additions have 

 been made to our knowledge of the subject by observation in this country 

 since then, but the general classification of the Delphinidas has been con- 

 siderably modified, so that it has become necessary to revise our lists. Un- 

 fortunately the great work of Van Beneden and Gervais, which was looked 

 forward to as likely to afford us an authoritative settlement of many difficult 

 questions, fails us in respect to the dolphins, owing to the death of Professor 

 Gervais before this section of the work was written. Professor Flower has, 

 however, taken up the subject in a masterly paper contributed to the Zoo- 

 logical Society,! and has done much in clearing the ground for more correct 

 observation and study of this most difficult class of animals. The key-note 

 of this revision by Professor Flower is that he places no dependence on the 

 number and size of teeth, or the form and proportions of the brain-case and 

 of the beak, all of which were the chief characters relied on by Dr. Gray, 

 and attaches most importance to the features presented by the palatal aspect 

 of the skull, and particularly the condition of the pterygoid bones, which, he 

 points out, in all the Delphinida3 enclose a large air-sinus. Adopting the 

 classification thus indicated, the following is the revised nomenclature of the 

 New Zealand Delphinidae : — 



1. Orca gladiator, Gray, p. 279. 

 (Orca pacifica, Gray, Proc. Zool. Soc, 1870 ; Hector, Trans. N.Z.Inst., vii., 260.) 

 Two complete skeletons of the Killer are now in the Museum, one having 

 been obtained from Tasmania and the other from the coast south of Wan- 

 ganui. I consider that there is no valid ground for separating the southern 

 from the northern species. The New Zealand species is the larger and 

 more robust of the two specimens, and measures 21 feet in total length. 

 The number of vertebras is as follows : — 



Cervical ... ... ... 7 First 4 anchylosed. 



Dorsal 



Lumbar 



Sacral 



Caudal 



11 



10 



15 



9 



52 

 The size of the skull exceeds by ^ that of the large skull in the Otago 

 Museum which I formerly described (Trans. N.Z. Inst., vii., 260.) 



* Trans. N.Z. Inst., ix., pi. xii. 

 t Proc. Zool. Soc. Lond., 1884, p. 



