PYCNODONTIDiE. 
253 
1853. Glossodus mantellii, 0. G. Costa, Atti Accad. Pontan. vol. vii. 
p. 28. 
1856. Ccelodus mantelli, J. J. Heckel, Denkschr. k. Akad. Wiss., 
math.-naturw. Cl. vol. xi. p. 203. 
Type. Jaws ; British Museum. 
A species of small or moderate size, known only by the dentition. 
Teeth of median series on vomer somewhat more than twice as 
broad as long, with a concave posterior margin, sometimes mesially 
constricted; teeth of two lateral series nearly equal in size, slightly 
elongated antero-posteriorly, and their width together not equalling 
that of the median series. Teeth of principal series on the splenial 
bone not more than twice as broad as long, scarcely equalling in 
width the two outer series, of which the innermost is nearly twice 
as wide as the outermost; a row within the principal series very 
rarely represented even by scattered small teeth. All the teeth, 
when unworn, with a deep apical pit, not crenulated on the 
margin. 
Form. Sf Log. Wealden : Sussex. Variety in Purbeckian : Dorset¬ 
shire and N. Germany h 
2690, 2698, 2709, 28415^ 28417. Series of eight type specimens 
described and figured by Agassiz, tom. cit. pi. lxxii. a. 
figs. 6-9, 11-14, wanting the original of fig. 10; 
Wealden, Tilgate Porest, Sussex. Mantell Coll . 
2700, 2707, 28416. Three specimens of the vomerine dentition, the 
first large and imperfect; Tilgate Porest. Mantell Coll. 
P.4392. Vomerine dentition, wanting outermost series of teeth; 
Tilgate Porest. Enniskillen Coll. 
49115. Two imperfect abraded specimens; Wealden, Tunbridge 
Wells. Mrs. Smith's Coll. 
1 A form of dentition very closely resembling that of Coelodus mantelli , from 
the Portlandian of Dept. Meuse, France, is also described by J. Cornuel, Bull. 
Soc. Geol. Prance, [3] yoI. viii. (1880), p. 151, pi. iii. figs. 1-15. He names 
two varieties of the vomerine dentition, “ Pycnodus mantelli, var. brevis ,” and 
“ var. stricta.” Other doubtful portions of vomers from the Neocomian of 
Haute Marne, Prance, are described by the same author, ibid. vol. v. (1877), 
p. 616, pi. xi. figs. 23-25, and F. J. Pictet, Mem. Soc. Linn. Normandie, vol. xvi, 
(1872), no. i. p. 18, pi. i. fig. 4. The species has also been recorded from the 
Wealden and Purbeck of North Germany on the evidence of splenials and 
vomers with widely spaced dentition and with the principal teeth much more 
transversely extended than in the typical English jaw (W. Dunker, Nord- 
deutsch. Wealdenbild. 1846, p. 65, pi. xv. figs. 19, 20, and C. Struckmann, 
Wealdenbild. Hannover, 1880, p. 89, pi. iii. figs. 6, 7). 
