252 
8IKEN0IDEI. 
1869. Ctenodus tuberculatus, T. P. Parkas & II. M oodward, Geol. 
Mag. vol. vi. p. 317, pi. ix. 
1809. Ctenodus ovatus, 1. P. Parkas, Scientific Opinion, vol. ii. p. 557. 
[Upper dental plate; collection of T. P. Parkas, Esq.] 
1870. Ctenodus cristatus, Hancock & Atthey, Nat. Hist. Trans. North- 
umb. & Durham, vol. iii. pp. 61, 92. 
1870. Ctenodus tuberculatus, Hancock & Atthey, ibid. p. 61. 
1872. Ctenodus tuberculatus, Hancock & Atthey, ibid. vol. iv. pi. xiv. 
1873. Ctenodus tuberculatus , T. P. Parkas, Coal Meas. Pakeont. p. 28 
figs. 83, 84, 92. 
1873. Ctenodus ovatus, T. P. Parkas, ibid. p. 28, fig. 89. 
1873. Ctenodus concavus, T. P. Parkas, ibid. p. 28, fig. 88. [Abraded 
upper dental plate; collection of T. P. Parkas, Esq.]. 
1874. Ctenodus cristatus, L. C. Miall, Quart. Journ. Geol. Soc. vol. xxx. 
p. 772, pi. xlvii. 
1875. Ctenodus cristatus, L. C. Miall, Ann. Mag. Nat. Hist [4] vol xv 
p. 436. 
1875. Ctenodus cristatus, J. Ward, [Proc.] N. Staffs. Nat. Field Club 
p. 244, figs. 1, 2. 
1875. Ctenodus tuberculatus, J. Ward, ibid. p. 246. 
1877. Ctenodus cristatus, W. J. Parkas, Proc. Iioy. Soc. N S Wales 
vol. x. p. 102. 
1877 Ctenodus tuberculatus, W. J. Parkas, ibid. p. 104 fig's, 1, 10, 11. 
23. 6 ’ ; ’ 
1877. Ctenodus ovatus, W. J. Parkas, ibid, p. 108, fig. 8. 
1877. Ctenodus concavus, W. J. Parkas, ibid. p. 106, fig. 4. 
1888. Ctenodus cristatus, A. Eritsck, Fauna der Gaskohle, vol. ii. 
p. 77, woodc. figs. 155, 156. 
1890. Ctenodus cristatus, J. Ward, Trans. N. Staffs. Inst. Mining 
Engin. vol. x. pp. 154, 156, pi. iii. figs. 3, 4. 
1890. Ctenodus cristatus, W oodward & Sherborn, Cat. Prit. Foss. 
Vertebrata, p. 51 (synonymy). 
Type. Palatine dental plate ; Leeds Museum. 
The type species. Palatine dental plate broad-ovate or elliptical 
in iorm, attaining a length of about 0 - 08 and a maximum breadth 
of about 0-04 ; inner margin gibbous or gently rounded ; coronal 
surface flat or slightly concave, with 12—14 acute, prominently 
tuberculated ridges, only slightly radiated; the tubercles laterally 
compressed. Mandibular dental plate relatively narrower and 
convex, similarly ridged. 
Form. Sf Loc. Coal-Measures : England and South Scotland. 
P. 5031. Imperfect skull exhibiting the upper surface, shown, of 
two-thirds the natural size, in PI. IY. fig. ] . Great Bow 
Coal, Clan way, North Staffordshire. The fragmentary 
remains and partial impression of a palatine dental plate 
