[759] 



XXV. — On the Occurrence of Ziphius cavirostris in the Shetland Seas, and a 

 Comparison of its Skull with that of Soiverby 's Whale (Mesoplodon Sowerbyi). 

 By Professor Tuknee. (Plates XXIX., XXX.) 



(Read 20th May 1872.) 



CONTENTS. 



Page. 



Historical Sketch of Ziphius cavirostris, . 759 



Description of Shetland Ziphius, . . 761 



Comparison of the Shetland Ziphius with 



previously recorded specimens, . . 768 



Page. 

 Historical Sketch of Sowerby's Whale, , 771 

 Description of the Skull in the Museum 



of Science and Art, Edinburgh, . . 772 

 Comparison of this Skull with previously 



recorded specimens, .... 776 



The illustrious Cuvier, in his treatise " Sur les Ossemens fossiles,"* described 

 and figured an imperfect skull which had been obtained, in 1804, by M. Raymond 

 Gorsse in the department of Bouches-du-Rh6ne, near Fos, on the southern 

 coast of France. It had been found on the sea-shore in the preceding year 

 by a peasant. Cuvier recognised it to belong to an undescribed genus of 

 cetaceans, to which he gave the name of Ziphius ; and from the deep hollow 

 which it possessed at the base of the rostrum, he named it Ziphius cavirostris. 

 From the condition of the bones, and the general characters of the specimen, 

 he judged it to be a fossil. Cuvier's description, though brief, and from a 

 mutilated specimen, yet clearly states the most salient features of the skull. 



This idea of the fossil nature of the cranium prevailed amongst zoologists until 

 1850, when M. Paul Gervais carefully re-examined Cuvier's specimen, and com- 

 pared it with the somewhat mutilated skull of a Ziphioid whale, which had been 

 stranded, in the month of May 1850, at Aresquies", in the department of 

 He'rault, on the Mediterranean coast of France.t From this re-examination 

 and comparison he not only pronounced Cuvier's specimen to be not a fossil, 

 but that the skull of the animal stranded at Aresquies was specifically identical 

 with the cranium from Fos ; and since that time the non-fossil nature of the Fos 

 specimen has been generally admitted. 



* Tome v. premiere partie, 350, fig. 3, pi. xxvii. Paris, 1825. 



t Annales des Sciences Naturelles, 3d series, xiv. 1850; also " Zoologie et Paleontologie Franchises," 

 l re ed. p. 154, et 2 me ed. p. 287. M. Gervais has, in order to give an opportunity for making a com- 

 parison, reproduced figures of Cuvier's specimen, both in his " Zool. et Pal. Franchises," and in pi. xxi. 

 of the " Osteographie des Cetaces." 



VOL. XXVI. PART IV. 9 M 



