104 
ACTINOPT'ERYGII. 
Ichthyodectes tenuidens, sp. nov. 
[Plate IX. fig. 6.] 
Type. Imperfect skull ; British Museum. Qra l 
A small species known only by remains of the head, 
border of maxilla and dentary nearly straight ; depth of denta J ^ 
symphysis not exceeding one quarter the total length of 4 be 
dibular ramus. Teeth very slender and smooth, with apex s & 
curved inwards. 
Form. Sf Loc. Turonian and (?) Albian : Kent. , 
49054. Type specimen, an imperfect head shown of the na ^ g 
size in PI. IX. fig. 6 ; Lower Chalk, Burham, Kent. ^ ^ 
fossil exhibits the superior and right lateral as ^ P . C r ( j; s . 
the head, but is transversely fractured and partial > 
placed at the front border of the orbit. The crania r ^ 
is narrow, exhibiting the usual median crest behind, 
the frontal bone of tho right side raised into a a 
tudinal ridgo. The frontals seem to extend backw.rr 
far as the hinder border of the orbit, and the ver> ■ ^ 
median ethmoid is conspicuous at the end of the s 
None of tho bones are externally ornamented. 
large size of the eye is indicated by fragments ° ^ 
ossified sclerotic (scZ.); immediately behind this are ^ 
remains of the thin cheek-plates ( s.o .), with traces 0 ^ . 
slime-canal which seems to have had radiating i ,r: ' n 
while in front may be observed the robust p 1 e r ^ 
( P r ■/•)) with its flattened inferior facette for the P a a 
The maxilla (iw.r.) is long and slender, but much f > ac ® 
so that its anterior end is displaced and only three 1 
slender teeth remain ; a facette postero-superioil) ■ ^ 
the extent of overlap of a supramaxillary bone. ^ 
general proportions of the mandible are indicate 0 » 
the anterior end of this is also fractured. At ^ jgtic 
physis and behind the fracture a few of the charac e ■ 
teeth are preserved. The outer surface of the ^ cnta '[ har p 
is smooth and only gently undulating, without an> 
longitudinal ridge. The preoperculum (p.°F-) 1S " „;n, 
to be much expanded, with thickened anterior m^ 
and the usual radiating branches of the season 1 
Smith 3 
Mrs 
41693. 
Fragment of jaw ; Lower Chalk, Hailing, Kent. „ 
Toulmin Smith ^ 
47227. Imperfect right dentary; Gault, Folkestone. Gardner Go 
