2 



BRITISH FOSSIL CETACEA 



'nodules,' 'concretions,' or 'cops' of the diggers^ are most abundant immediately 

 over the ' rough stones.' 



It will be imderstood that I use here, as in my 'Memoir' of 185G, the term ' Red 

 Crag' in the sense in which it was first aj)plied by l^dward Charlesworth, Esq., F.G.S., 

 as " characterised by its ferruginous colour ;" ' fully recognising, with the same perse- 

 vering and accurate explorer of the Eastern Counties' Crag-beds, that the rolled and frag- 

 mentary Cetacean remains belong to a deposit older than those which, by their testaceous 

 fossils, may be truly or strictly defined as ' Red Crag :' that the older deposit in question — 

 more or less destroyed and broken up in Suff'olk — answers, in time, to the better preserved 

 Belgian ' Sable noir' of the ' Systcme Diestien' of Nyst and von Kocncn and also that, 

 though I have received Cetotolites from the London Clay of Essex, I hold the same opinion, 

 as does Prof. Van Beneden in regard to his ' Fiacozip/iius,' from the ' Rupelian Clay' of 

 Edeghem,* that they have gravitated into such older deposits in the course of their 

 agitation and rolling by the surf-waves. 



By the term ZipJiius I understand, with Cuvier, a genus having close relations with 

 Ph^seter,\Awn., and still closer with Hyper oodon, Lacep.'^ (if it really merit generic distinction 

 therefrom), characterised by a more or less elongate, slender, edentulous, beak-shaped upper 

 jaw, or ' rostrum, varying in form, abruptly and considerably expanding between the 

 orbits, behind which both maxillaries and preraaxillaries rise to build, with the frontals, a 

 boundary wall concave upward and forward, the middle part of which, formed by the 

 premaxillaries and nasals, arches forward, so as more or less to overhang the nostrils.7 In the 

 mandible or lower jaw the teeth are reduced usually to a pair, which are subterminal or 

 terminal in position, and are most conspicuous, or may only be visible, in the male sex.^ 



In the existing species of this genus, discovered since the date of the classical 



1 An abbreviation, according to our Saxon proclivity, of ' coprolites,' which these nodules were generally 

 supposed to be prior to my discovery, in 1840, of the nature of the coprolitoid fossil in Mr. John 

 Brown's collection, afterwards figured in ' British Fossil Mammalia,' p. 536, figs. 219, 226, and 227. 



- 'Proceedings of the Geological Society of London,' vol. ii (May, 1835), p. 196. 



3 'Geological Magazine,' 1867, vol. iv, p. 501. 



* See the excellent Memoir by Mr. Godwin-Austen, 'Quart. Journ. Geol. Soc.,' vol. xxii, 1866, p. 228. 

 Ziphius — " a de grands rapports avec le cachalot et encore de plus grands avee I'hyperoodon." 



— 'Ossem. Foss.,' torn, cit., p. 351. 



" " La partie du museau formee comme a I'ordinaire par les maxillaires et les intermaxillaires, est una 

 espece de cyliudre ou de prisme quadrangulaire dont les angles sont arrondies." — Ibid., torn, cit., p. 354. 



7 " Ces intermaxillaires — rcmontent Ic long des cotes des narines, et se recourbent en avant pour former 

 avec les deux os du nez, n, n, qui sont encastres entre eux, unc espece d'auvent sur le dessus des narines." 

 —lb., p. 351. 



* The taxonomic applications of the teeth in the species of Ziphius is affected by the singular arrest of 

 development of the dental system. Rudiments of teeth may be found hidden in the gum, filling the alveolar 

 groove of the premaxillaries, from which one small pair may slightly project, according to the age of the 

 individual. Small teeth, or concealed rudiments, may precede or follow the pair, or two pairs, which are 

 better developed in the lower jaw. As generic characters, I deem these dental conditions to be valueless. 



