SILURID^. 
335 
A small species, known only by the imperfect head. External 
ornamentation of bony plates much like that of A. egertoni^ but 
the tubercles more numerous, more rounded, less united by reticular 
ridges, and more definitely arranged in radiating lines. Supra- 
occipital bone rather broad, not impressed by the slime-canals. 
Form. Log. Upper Eocene : Barton Cliff, Hampshire; Headon 
Hill, Isle of Wight. Oligocene : Germany. 
A fine portion of cranium of this species, in the Museum of Practical 
Geology, is described by Hewton, loc. cit. 
28094. Eleven otoliths, including two figured in Part I. PI. IV, 
figs. 4, 5, one of these and two others also figured by 
Newton, loc. cit. figs. 4-6, as of doubtful species ; Barton 
Clay, High Cliff*, Hampshire. 
Presented^ hy F. E. Edwards, Esq., 1852. 
29023. Pour otoliths ; Chutan, Hampshire. Cowderoy Bequest. 
40283, P. 376. Otoliths, probably either of this or the next 
species; High Cliff. Ediuards Coll. 
Arius (?) bartonensis, A. S. Woodward. 
1887. Arius (?) bartonensis, A. S. Woodward, Geol. Mag. [3] vol. iv. 
p. 306, fig. 3. 
Ty'pe. Dorsal fin-spine ; British Museum. 
A very small species, of uncertain genus, known only by fin- 
spines. Dorsal fin-spine slender, much laterally compressed, finely 
striated on the sides, with recurved denticles on the anterior and 
posterior margins towards the apex, which curves a little forwards. 
Form. ^ Loc. Upper Eocene : Barton, Hampshire. 
40280. Type specimen described and figured loc. cit., and five other 
imperfect fin-spines of which two are pectoral; High Cliff', 
Barton. Ediuards Coll. 
P. 1894 a. Larger dorsal fin-spine, imperfect at the apex, noticed 
loc. cit. Egerton Coll. 
P. 6500. Dorsal fin-spine ; Barton. Purchased, 1891. 
Arius iheringi, A. S. Woodward. 
[Plate XVII. fig. 4.] 
1898. Arius iheringi, A. S. Woodward, Rev. Mus. Paulista, vol. iii. 
p. 64, figs. 1, 2. 
Ty'pe. Impression of skull; British Museum. 
