ZIFHUDX. 327 



I should have preferred Hjiperoodontido' for tlie name of this familj-, 

 as Hijperoodon is the oldest genus ; but it conveys a false impression, 

 caused by a slijJ of the pen in describing the teeth in the manuscript 

 (or an error of the press in the work) of Otho Fabricius, 



Synopsis of the G-es^era. 



A. Teeth2 or 4, in front end of the lower Jaiv, conical. Beak of skull with a 

 high crest on each side, formed by the elevation of the maxillary hones. 

 Hj^eroodontina. 



1. Hyperoodon. Beak of the skrdl steaigikt ; crest of the beak sharp- 1^^-j^^ '^'^ 



edged above, as high as the occiput. ' 



2. Lagenocetus. Beak of the skull aseeBding; crest of the beak flat- 



topped, higher than the occipital. >/ni,i(t^ 



B. Teeth 2 or 4, m f-ont end of the loicerjair, coincal or cylindrical. Beak 



of skull simple ; interntaxUlaries enlaryed behind, fonniny a more w 

 less dee2) cavity round the blowers. Epiodoutina. 



8. Epiodon. Vomer simple, smallau; intermaxillaries elevated, and 

 forming a moderately deep, well-marked basin round the blowers. 



4. Petbohhynchts. Vomer swollen, foiTaing a lai'ge, elongated tubercle 



between the callous intemiaxillaries ; intemiaxillaries forming a deep 

 basin romid the blowers. 



C. Teeth in the side of the lower jaw, compressed. Beak of skull simple; 



interma.ullaries linear, rather swolkn on side of blowers. Ziphiina. 



5. BEHAHDirs. Teeth in the front of the side of the lower jaw; lower 



jaw simple, tapering. 



6. ZiPHius. Teeth in the middle of the side of the lower jaw; lower 



jaw simple, tapering. 



7. DioPLODOX. Teeth in the middle of the side of the lower jaw. Lower 



jaw broad behind, suddenly contracted in front. 



A. Teeth 2 or 4, in the front end of the lower Jaic, or often hidden in the 

 gums. Beak of skull with a high crest on each side above, formed by 

 the elevation of the ma.rilhiry hones. Eyes close to the gape. Cerviad 

 vertebra all anchylo.<ed. Hyperoodontina. 



Hj'perodontina, frray, Proc. Zool. Soc. 1863. 



Ilvperodontina(pars), Gray, Zool. Ereh. ^- 7V>T. 24 ; Cat. Cetac. B.yi. 



'iP.'iO, ; Froc. Zool. Soc. 1864, 2-39. 

 Diodonea (pars), Rajin. Anal. Nat. 60, 1815. 

 IvCs Ileterodontes, Duvernoy, Ann. Sci. Xat. 1851, xv. 23; Arch. 



Naturg. 1852, 21. 



