628 SIR SIDNEY HARMER ON COMMERSON's DOLPHIN 



Other authors of the early part of the last century are unable to 

 do more than quote the original account, although Gray (1846, 

 p. 30) surmised that this Dolphin might be identical with his own 

 Beluga kingii. 



The external characters of the species which forms the special 

 subject of this paper were admirably figured by Moreno (1892, 

 pi. ix.), who described it (p, 385) under the name of Lageno- 

 rhynchus floweri, and gave satisfactory figures of the skull 

 (pi. viii.). It was first observed by him, in October 1874, in the 

 bay of the River Santa Oruz, which is on the Patagonian coast, 

 almost in the same latitude as the Falkland Islands. It was 

 seen in hundreds on certain occasions, but no specimen could at 

 first be obtained, although a female, the original of the three 

 figures of the larger individual shown in pi. ix., was secured from 

 the same locality in December 1876, and two other specimens 

 were obtained from Tierra del Fuego or Santa Cruz in 1884. 

 The colour-markings were identical in all the sjDecimens. The 

 individual whose external measurements are recorded was 138 cm. 

 in length, and the total length given for the skull is 28 cm. 



It is unfortuna,te that Moreno's specific name, which was based 

 on a good and well-illustrated account of external and cranial 

 characters, cannot be accepted. It must be regarded, I think, 

 as a synonym of Delphinus comviersonii, which, although 

 described inadequately and without illustrations, appears to be 

 perfectly recognisable in the light of the evidence now available. 

 Not only were Commerson's and Moreno's specimens from 

 substantially the same locality, but the silvery colour, with black 

 confined to the " extremities,", described by the earlier observer, 

 is equally noticeable in Moreno's figures, which represent an 

 animal mainly white, with the head, tail, flippers, and dorsal fin 

 black. 



The only other actual description of this animal with which I 

 am acqiiainted is that of the late Dr. W. S. Bruce (1915, p. 500, 

 pi. i.), who shows the external characters of a specimen, 4 ft. 4 in. 

 in length, which was obtained by him in 1893 at Poi-t Stanley, 

 Falkland Islands. It was referred, doubtfully, to Lagenorhynchihs 

 cruciger (d'Orb. &, Gerv.), and it was styled the " Piebald 

 Porpoise." Dr. Bruce records a number of positions to the 

 south of the Rio de la Plata at which Dolphins believed to be 

 " Piebald Porpoises " were observed from the ship. 



It is shown by the records of Moreno and Bruce, as well as by 

 the new evidence now submitted, that a Porpoise characterised 

 by its sti'ongly contrasted black and white colours arranged in a 

 very definite j)attern, is common in the neighbourhood of the 

 Falkland Islands and of Tierra del Fuego. I think there can 

 be no doubt that this Porpoise belongs to the same species as 

 the " Jacobites " which played round Bougainville's ship in the 

 Straits of Magellan, and were observed later at the Falkland 

 Islands by Quoy and Gaimard, and by Lesson. 



