6. zipnitrs. 349 



high ; hinder wing of the maxilla expanded, horizontal ; palate 

 smooth ; lower jaw broad behind, narrowed and bent in front of the 

 lateral teeth. Tympanic bones large, very thick, free edge open and 

 much twisted (see Van Beneden, Mem. Acad. Brux. 8vo, xvi. fig. at 

 p. 41 ; and Dumortier, Mem.). 



Ziphius, Gray, P. Z. S. 1804, .341. 

 (5 . Zipliius, Cuvier, Oss. Fuss. v. 350 ; Gray, Zool. Erehus 8f Terror, 27 ; 

 Cat. Cetac. B. M. 1850, 70 ; P. Z. S. 1864. 

 Diodon (pars), Lesson, Tab. H. A. ; Bell, Brit. Quad. 499. 

 Anodon (pars), Lesson, Tab. R. A. 

 Heterodon (sp.). Lesson, 3Ian. 3Iamm. 

 DelphiuorlijTichus (sp.), Gray, Ann. ^- 3Iay. N. II. 1846. 

 Physeter (sp.), Soio. Brit. 3Iisc. 1. 

 Mesiodon, Duvernoy, Ann. Sci. Nat. 1851, xv. 

 Diplodon (part), Gervats, Zool. et Puleont. Franq. 



$ . Nodus (sp.), Wagler, N. S. Amph. 34, 1880. 



Delphinorhynclius, Blainv. ; Rujyp, Cetac. ; Gray, Zool. Ereb. ^- Terror ; 



Cat. Cetac. B. M. 1850, 73. 

 Delphinorhynclius (sp. ), F. Cuvier, Cetac. 114. 

 Aodon, Lesson. (Ein-r. Baffoii. 

 Heterodon (sp.), Blainville ; Lesson, Man. 

 Delphinus (sp.), Blainville; Desm. 3Iamm. 



M. Dumortier considers the dentation on the skin of the ui:)per jaw 

 to be I'epresentative of the horny protuberances on the membrane of 

 the palate of Hyperoodon. — 3Iem. Ac. Brux. xiii. p. 8. 



The lower jaw of the young female taken at Ostend had no ap- 

 pearance of teeth ; but when the lower jawbone was examined it 

 exhibited, near its middle, a large alveolar groove, as if giving origin 

 to some teeth ; the larger specimen found at Ha\Te had rudimentary 

 teeth at the base of the alveolar of the lower jaw, which is placed in 

 the same relative situation as in the Ostend specimen. 



Cuvier (Eegne Anim. ed. 2, 288) says that these animals lose theii- 

 teeth early. M. Dumortier thinks this is a mistake, and that, on 

 the contrary, the teeth are not cut through the gums until they 

 acqrdre their full size. 



The skeleton of the female is described and figured by M. Van 

 Beneden, Mem. Acad. BruxeUes, 8vo, xvi. 1863. 



The skull (as remarked by M. Cuvier, see Van Beneden) much 

 more resembles that of Delphinus than Hyperoodon. The animal is 

 at once known from the latter genus by the head not being convex 

 and rounded in front, and by the teeth being in the middle and not 

 at the end of the jaws. 



Blainville, when he first saw the animal on the coast of France, 

 considered it the same as Dale's Hyperoodon, and F. Cuvier follows 

 him ; but M. Cuvier pointed out, in the ' Regne Animal,' the dif- 

 ference in the form of the skull of the French animal. 



This geniis is very like Delphinorhynclius, but is easily known by 

 the teeth being in the middle of each side, and the peculiar form of 

 the lower jaw. 



Mr. BeU, following Lesson in adopting his heterogeneous genus 

 Diodon, has considered Sowerby's whale a distinct genus from 



