254 
ACTIN0PTERYG1I. 
of 
Opisthopteryx gracilis, Pictet & Humbert. 
I860. Mesogaater gracilis, F. .1. Pictet, Poiss. Foss. Mt. Libau, p- 3 > 
pi. iii. fig. 2. 
186<i. Opistopteryx gracilis, Pictet & Humbert, Nouv. Kech. P 01 
Foss. Mt. Libftn, p. 80, pi. xi. figs. 1-4. . r.y] 
1887. Opistopteryx gracilis, J. W. Davis, Trans. Koy. Dublin boc. L i 
vol. iii. p. 569, • 3 
1887. Opistopteryx curtus, J. W. Davis, ibid. p. 560, pi. xxxii. fig- 
[l‘ish distorted by crushing; Edinburgh Museum.] 
rype. Distorted fish, wanting caudal fin ; Geneva Museum. 
The type species, attaining a length of about 0*1. Peng ^ 
head with opercular apparatus equalling about twice the maxim ^ 
depth of the trunk and contained approximately four times in^ 
t otal length of the fish. Longest ray of pectoral fins extending 
tho origin of the pelvic fins, which are about two thirds as a^n 
as the pectorals and arise midway between the latter and the ui 
dorsal fin deeper than long, with about 11 rays, its origin a. ^ 
Irom the occiput as is its termination from the base of the Cliu .^ 
fin ; anal fin nearly as deep as the dorsal but less extended, 
only about 8 rays, arising midway between the pectorals an 
caudal. , 
The fossilised examples of this fish are usually much distor^^ 
but its general characters and proportions seem to be coir 
stated in the above diagnosis. One specimen, evidently s or 
by crushing, is described by Davis under a distinct specific n. 
O. curtus. 
Form, <Sf Loc. Upper Cretaceous : Mt. Lebanon, Syria. 
P. 1886 . Fine specimen slightly elongated by crushing, displ-0^ . 
the separate neural spines in the abdominal l0p 1 ,, 
Sahel Alma. Egerton W 
49604 . Another fine specimen with head and anterior abd°m^^ 
region distorted ; Sahol Alma. Traces of the re a 1 
. . 7. *4lltS C J J 
large, pointed gill-rakers are seen. 
Lewis 
amen 8 * 
47357 - 58 , 47816 , 49594 . Four more imperfect distorted speci 
with traces of the minute teoth and well-develop e » „ 
with traces of the minute teoth and 
rakers ; Sahel Alma. 
Lewis 
. Coll- 
Genus SCOPELOIDES, Wettstein. 
[Fischfauna Tertiaer. Glarnerschief. 1886, p. 55.] 
Head large and trunk elongate-fusiform. Mandibular 5^ e j v 
sorium much inclined backwards ; jaws slender ; teeth mo 
