1882.] WHALES OF THE GENUS HYPEROODON. 723 



bidens, butskopf, dalei, borealis, &c.'; and, though allied to Berardius, 

 Mesoplodon, and Ziphius, and also, though less closely, to Physeter, 

 its strongly marked differential characters have, since the early part 

 of tlie century, thoroughly established its generic isolation. 



It is well known to pass the summer months in the Arctic Seas 

 which lie to the north of the Atlantic, and to migrate southward 

 in the autumn, although its actual winter quarters do not seem 

 to have been ascertained. Scarcely a year passes without one or 

 more specimens having been taken or stranded on some part of 

 the coasts of the British Isles, usually in the months of September 

 and October. Similar captures have also been recorded upon other 

 parts of the coasts of Eastern Europe, such as Norway, North Germany, 

 Holland, and the north of France. From this point they seem "to 

 leave the shore ; for no authentic instances are recorded of their 

 occurrence on the west coast of France, or of Spain, or in the Medi- 

 terranean. Most of the specimens thus seen, or at all events taken, 

 are solitary individuals, generally young ; but not unfrequently two 

 are met with together, an adult female accompanied by her young, 

 the former often falling a victim to her maternal solicitude for the 

 welfare of the latter. 



Of the external characters of this common form of Hyperoodon, 

 which usually attains a length of from 20 to 25 feet, many descrip- 

 tions and drawings have been pubhshed ; and there are few osteo- 

 logical museums of any importance which do not possess a skeleton 

 of it. The earliest figure, made with really scientific accuracy, is 

 that published by John Hunter in the ' Philosophical Transactions ' 

 for 1787, from the individual (a female 21 feet long) taken in the 

 Thames in 1/83, the skeleton of which is still preserved in the 

 Museum of the Royal College of Surgeons. 



Hunter, in his classical memoir on the Cetacea, says, speaking of 

 this specimen: — "The one which I examined must have been young 

 [as is proved by the condition of the skeleton] ; for I have a skull of 

 tbe same kind nearly three times as large, which must have belonged 

 to an animal thirty or forty feet long." This skull has unfortunately 

 not been preserved ; but portions, evidently belonging to the same 

 individual, are still in the Museum. Of these the anterior part of 

 the lower jaw, of great density and containing the two teeth, the 

 great age of which is attested by the solid condition of their bases, 

 was catalogued by Professor Owen as that of an "immature" animal". 



No notice appears ever to have been taken of Hunter's reference to 

 this large specimen, or of the existence of any form oi Hyper oodon 

 different from that commonly known, and of which more detailed 

 descriptions were given by Vrolik ^, Wesmael ', Eschricht^ Thomp- 



^ Balanarostrata, Ohemniz, Beschaft. der Berlin. Gesellsehaft Naturforscher, 

 iv. p. 183 (1779) ; Delphinus bidentafus and Belphinus huUlcopf, Bonnaterre, 

 'Cetologie,' p. 25 (1789); Delphinus diodoti, Lacepede, 'Hist. nat. des 

 Ctitaces," p. 309 ; and Hypcroodon buisJcopf, idem, ibid. p. 319 (1804). 

 - Descriptive Catalogue of Osteological Series, vol. ii. no. 2480 (1853). 

 3 Nat. Verhand. Maatscli. Haarlem, 2. Verz., D. 5 (1849). 

 NouT. Mem. de I'Acad. Eoy. de Bnixelles. siii. 4. p. 1 (1841). 

 Untersuchungen iiber die nordische Wallthiere, 1849. 



