222 
ACTINOPTERYGII. 
Type. Imperfect ectopterygoid ; British Museum. 
The type species, not satisfactorily definable, with cranium 
attaining a length of about 0-15. Maximum width of cranium 
slightly exceeding one third its length, and premaxilla ornamented 
with radiating tuberculated ridges. All tho teeth of the ecto- 
pterygoid, except the few small ones posteriorly, moderately slender 
and slightly barbed; tho largest tooth of the inner mandibular 
series situated within the anterior half of the deutary. 
Form. Loc. Senonian and Turonian : Sussex and Kent. 
4039. Type specimen described and figured by Agassiz, Joe. cit ■ > 
Chalk, Lewes. This is the hinder half of the left ect.o 
pterygoid exposed from withi 
Mantell Coll- 
P. 5491. Imperfect skull and mandible, noticed by the present 
writer, loc. cit. p. 317 ; Chalk, Lewes. The specimen m 
damaged by an oblnjue fracture, and the rostral region 
the cranium is obscure; but the frontal bones aie w c 
displayed and shown to extend close to the occrp 1 11 
border. Only a trace of the small supraoccipital, with i 
hinder keel, is preserved. There is a shallow, an tor 
posteriorly elongated fossa above the otic region on eae^ 
side, fragmentary remains of the premaxilla on ea-^ 
side prove it to have been an antero-posteriorly elonga ^ 
laminar bone, bent, inwards above on its long axis, 
ornamented externally with tuberculated radiating n n e _^ 
The long and slender maxilla, which is almost smoot 
nearly complete on the left side, and extends t<JI 
above the premaxilla to about the middle point o ^ 
latter. Neither the maxilla nor the premaxilla, as ^ ^ 
, served, exhibits any indications of teeth. Ike imp ^ 
mandible is seen from beneath, and two ot its ■ ^ 
recurved teeth are exposed. There are also remains 
the pterygo-palatine arcade, with several of the c ^ ra ^ aseff 
istie barbed teeth, and with marks of tho ova ^ 
of attachment of similar teeth which have been * 
away. Tho slender ceratohyal is preserved on a 
side ; while immediately above it is exposed P ar e( j 
laminar bone, probably entopterygoid, hearing ® u „ 
minute teeth. ’ EnnidetUm 
P. 1810 a. More fragmentary skull and mandible, g en t. 
Loomis, Palasontogr. vol. xlvi. (1900), p. 207 ; C a 
The maxilla does not exhibit any teeth ; but a i<o 
