MASTODON ARVERNENSIS. 33 



more especially in figs. 4 & 5 of PI. XVI., figs. 1, 2, 3, & 5 of 

 PL XIX., and figs. 2 & 6 of PI. XXI. of his work above quoted. 



Of the other true molars, i.e. the antepenultimate and 

 penultimate, various specimens, more or less perfect, have been 

 yielded by the Crag. Several existed in Mr. Robert Fitch's 

 interesting collection at Norwich when I examined it in 1846, 

 and probably a considerable addition has been made to it 

 since. Two of these are figured in the ' British Fossil Mam- 

 malia ' (pp. 280,281). Fig. 98 is described by Professor 

 Owen as the penultimate upper. The anterior portion is 

 broken off ; what remains of the crown shows four ridges and 

 a talon. But for the position assigned to it by so able and 

 practised a palaeontologist, the figure would convey the im- 

 pression of its being a lower instead of an upper molar, from 

 the narrowness of the crown in comparison with the width, 

 and from the form of the hind talon. Fig. 99 represents a 

 corresponding penultimate lower molar, also from Mr. Fitch's 

 collection. Both teeth — the one of which has the crown re- 

 presented in plan, the other in profile— show in a strongly 

 marked manner the characteristic alternation of the mammillae, 

 which is never seen in the corresponding molars of the Eppel- 

 sheim species. Moreover, the mammillae are more elevated, 

 their conical isolation more defined, and the enamel layer 

 thicker than in M. (Tetraloph.) longirostris. There is a pecu- 

 liar wavy and finely grooved rugosity of surface, which is seen 

 on the enamel near the basis of the crown and ' bourrelet ' 

 where it exists in the molars of the Crag Mastodon (see PL 

 IV. fig. 4), and of the nearly allied Indian species M. (Tetra- 

 lophodon) Sivalensis. It may be compared to the appearance 

 yielded by a bound book when the edges of the leaves slightly 

 overlap, and they are bent in a flexuous curve. This peculiar 

 rugosity is not nearly so conspicuous in the Eppelsheim 

 species, nor in the M. (Trilophodon) angustidens of Simorre. 



The finest English specimen of one of the ' intermediate 

 molars ' of the Crag Mastodon that has come under my obser- 

 vation is a germ of the penultimate true molar (upper jaw, 

 right side), lately discovered by the Rev. Mr. Marsden in the 

 bed of coprolitic or phosphatic nodules in the parish of Ramsey 

 in Essex, about three miles west of Harwich, and kindly 

 lent to me for description. It is represented (about two-ninths 

 of the natural size) by figs. 1 & 2, PL IV. of the accompany- 

 ing illustrations. It consists of the shell of the crown quite 

 entire, the nucleus of the ivory core not having become fully 

 calcified, nor any of the fangs developed. The crown pre- 

 sents four intact ridges, with a front and a back talon. The 

 mammillae of the outer and inner lines are very high, and 

 converge as they ascend, so that the apex of the crown is 



VOL. II. D 



