of Mount Lebanon. 245 
racters were continued in the Cretaceous and following periods 
by the family of the Halecoids. 
Our Lebanon faunas are rich in fishes of this family ; for out 
of fifty-one species now known, nineteen belong to it. 
Another important type is that of the Teleostean fishes with 
serrated scales, united by M. Agassiz under the name of Ctenoids. 
This denomination, which, at the present day, does not corre- 
spond to an order of sufficient zoological value, may, however, 
still be advantageously employed, in the general comparison in 
which we are now engaged, to designate all those fish which 
more or less approach the Perch-type in this serrated form of 
scale, in the spinous rays of their fins, in the tendency of the 
bones of the head to develope points, &e. 
These fishes, less numerous at the Lebanon than the Hale- 
coids, present, however, as we shall now show, certain very dis- 
tinct forms ;.they have, however, a common uniform physio- 
gnomy, and resemble each other much more than the recent 
Ctenoids. Variation set in at a later period, and has gone on 
constantly augmenting to the present day. 
The types of prickly-finned fishes which we find at Mount 
Libanus are the following :— 
1. The group Beryz, the singular history of which has already 
been made known by M. Agassiz. At the present day they form 
part of a small cluster of genera (Holocentrum, Myripristis, 
Beryx) specially belonging to the Indian seas, allied to the 
Percoids by their more essential characters, but constituting in 
that family a tribe characterized by the branchiostegal and 
ventral rays, which exceed the normal number of seven. This 
Beryz-group, comprising the recent genus and some extinct 
ones, is the sole representative of the Percoid family during the 
Cretaceous period. It then existed as the first expression of that 
family, now so abundant; and after having then constituted it 
entirely, now exists only as an accessory branch of the same. 
2. An interesting and entirely new type, which we have de- 
signated Pseudoberyx. (To the normal characters of Berya it 
unites that of having the ventrals abdominal—a circumstance of 
rare occurrence in true prickly-finned fishes. May we not see 
in this circumstance an indication of a rule similar to that which 
we have established in the case of the Halecoids, and infer that 
the first manifestations of types have in general exhibited the 
tendency to approach the archetypal forms more than the later 
generations have done? 
3. The type of Pycnosterinz, already established by Heckel, 
which in its characters approaches the family Chromidz, formerly 
associated partly with the Labroids, partly with the Sciznoids, 
but subsequently recognized as distinct, and removed to the group 
