476 PROK. FLOWER ON THE DELPHINID^. [NoV. 20, 



is peculiar in the deep indentation between the lobes of the caudal 

 fin, and especially in the dorsal fin being rounded in outline, un- 

 like that of any other known Cetacean, but rather resembling the 

 adipose fin of a Salmon on a large scale. Ilutton simply describes 

 the dorsal fin as " truncated." Both Hector and Hutton describe 

 the distribution of the white markings on the black surface as in 

 D. heavisidii, but with this striking difference, that in the New-Zea- 

 land animal the " nose and forehead is pure white," bounded by a 

 crescent of black behind the blowholes. The teeth also appear to 

 be more numerous, being usually 31 and sometimes 32 on each side 

 of each jaw, A statement made by Dr. Hector that " the cervical 

 vertebrae are ankylosed into a solid mass, 1"3 inch in length," is 

 also very important, but requires elucidation and confirmation. 



An important contribution to our knowledge of the animals of 

 this group has been lately made by tiie publication by Van Beneden 

 (Bull, de I'Acad. Roy. de Belgique, 3me ser. t. i. no. 6, juin 1881) 

 of a description and figure of the external characters, with osteological 

 details, of a " Nouveau Dauphin de la Nouvelle-Zelande," which, 

 misled by Hector's identification of the common Cephalorhjnchus 

 of the seas around that land with Gray's Electra clancula, he has 

 named Electra hectori. But the description of the skull, the form 

 of the pterygoid bones (a drawing of which Prof. Van Beneden has 

 most obligingly sent me), and especially the number of the vertebrae, 

 show that it is widely removed from the Lagenorhynchi, and must 

 enter into the group of Cephalorhynchi. In fact Van Beneden says 

 that " la tete est parfaitement conforme a celle qui est represeutee 

 sous le nom de Cephalorlujnchus heavisidii (' Osteographie,' Atlas, 

 pi. xxxvi. fig. 1)." He further states : — " Si nous comparons le 

 dessin du crane et du corps avec les figures publiees par M. James 

 Hector sous le nom de Electra clancula, nous trouvons une similitude 

 presque complete avec cette espoce : le crane offre exactement la 

 menie conformation et les dents se correspondent par le nombre 

 comme par la forme." The dorsal fin has almost exactly the same 

 rounded form, though with less elevation, and the caudal fin the same 

 deep indentation between the widely divaricated lateral lobes. The 

 coloration appears only to differ in the ujiper and anterior part of 

 the head and beak being black instead of wiiite, as in Hector's spe- 

 cimens. In this we have a return to the original figures of 

 D. heavisidii and D. hastatus. From Rapp's figure of the latter, 

 however, Van Beueden's differs in the under surface of the chin and 

 throat being white instead of black. The teeth are '-^, the largest 

 being 2 miUim. in diameter. The vertebrae are C. 7, D. 14, L. 15, C. 

 27; total 63. The atlas and axis are united, the remainder of the 

 cervical vertebrae free. The manus is narrow, the first and fifth digits 

 being quite rudimentary. The following are the numbers of the 

 elements of each digit, including metacarpals: — I. 1., II. 6, III. 4, 

 IV. 3, V. 1 ; the individual described was, however, very young, being 

 only 3 feet 6 inches in length, and therefore all the phalanges may not 

 have been ossified. 



