208 
ACTINOPTEKYGII. 
of preoperculum short and stout ; postclavicular plate triangular, 
somewhat longer than deep, and its postero-superior margin ex- 
cavated. Pectoral fin arising just above the postclavicular plate, 
the large pelvic fin immediately behind this plate and in advance of 
the origin of the dorsal fin ; dorsal fin somewhat deeper than loo-- 
comprising 12 rays, and the distance between its hinder end an 
the caudal fin slightly exceeding that between its origin and the 
occiput ; anal fin smaller than the dorsal, at least as long as deep, 
comprising 18 rays, and arising much neater to the caudal than to 
the pelvic fins. Three large dorsal plates behind the occiput, o' ate 
in torm, very slightly overlapping, ornamented with closely 
arranged concentric rows of tubercles, and not quite reaching t ' 
dorsal fin; lateral scutes much smaller, irregularly triangular an 
deeper than broad, perforated by the sensory canal. 
Form. Loc. Upper Cretaceous : Uakel, Mount Lebanon, Sj ria. 
49478. A vertically crushed specimen, displaying the head 
opercular bones as shown in PI. XI. fig. 7. The cran ^ 
roof is shown partly from within, partly in imp ress, ° n ° 
the outer ornamented face; but it merely exhibits 
large extent of the frontals (/»•.), not distinctly indicating 
the other elements. The extended premaxilla J 
deepened in front and tapering behind, is conspicuous 
each side and exhibits the single series of small s en 
teeth, fixed on tumid bases. On the left side the s ' en 
maxilla (mx.), with small teeth in its hinder portion, 
seems to he partly preserved. The orbit ( o .) is ' K,u '\ . ,j 
behind by a chain of small, tuberculated circunior 
plates (eo.), of which four are preserved ; while " . g 
of the cheek between these and the preopcrcu 
covered by posterior suborbitals (s.o.), of which the 1 ^ 
are not clear. Both mandibular rami are exp 0 ' 1 ' ^ 
within and exhibit the characteristic teeth on tumi 
while that of the right side shows two irregular P 
nences of hone at the tapering symphysis. Eac ^ ^ 
gradually deepens behind and seems to consi» 
elements, dentary (d.) and articulo-angular (<#*)> ° u k erC u- 
the limits are indicated by the impression of the u ^ . 
lated outer face of the left side. The preoperculum 
is a thickened vertical rod, almost reacliing t e gtoUt 
roof above, and terminated below by the short at 
posteriorly-directed spine ; a narrow tuberculaU r , 
extends along its posterior margin. The trian D u a 
