of Mount Lebanon. 241 
2. The existence of a certain number of genera or groups, 
which, as far as we know at present, characterize the Cretaceous 
epoch. Such are the genera Scombroclupea and Leptosomus, the 
groups of Dercetis and Eurypholis. 
3. The great number of extinct genera which contribute to 
give these faunas a special physiognomy. These are, at Hakel, 
Pseudoberyx, Petalopteryx, Coccodus, Aspidopleurus, and Cyclo- 
batis; and at Sahel Alma, Pyenosterinz, Cheirothriz, Rhinellus, 
and Spaniodon. 
4, The fact that among the genera which are still represented 
by living species, those which are the most abundant at the Le- 
banon are precisely such as belong also to the Cretaceous epoch. 
We may mention in particular the type Bery#, which is pre- 
eminently Cretaceous, although represented at the present day 
by some species in the warmer seas. We may also cite the 
Clupee, the existence of which is demonstrated as far back as the 
Cretaceous period, and the Chirocenirites, the maximum develop- 
ment of which is equally characteristic of that epoch. 
The fish which are not referable to one or other of these cate- 
gories are very few in number, and occupy but a subordinate 
position in the Lebanon faunas. 
But, although we are tolerably certain of the general fact that 
these faunas are Cretaceous, we find it a much more embarrass- 
ing matter to decide’to which of the subdivisions of this long 
age they should properly be referred. The history of fossil fish 
presents still too many breaks to admit of our applying here the 
same methods as hold good in the case of Mollusks and Eehi- 
noderms, and we are forced to content ourselves with a certain 
degree of probability. 
The first point to determine is that no species of Mount Li- 
banus has ever yet been found in any other deposit, save certain 
parts of Syria and Asia Minor which belong to the same epoch, 
and of which we have already spoken. Consequently our com- 
parisons become limited to the more uncertain relations between 
genera and natural groups. 
We have compared the faunas of Lebanon with that of Voi- 
rons (as made known by one of the authors*), with that of Co- 
men in Istria (as studied by MM. Heckel, Kner, and Stein- 
dachner), with that of the Chalk of England, and finally with 
that of the Chalk of Westphalia (the numerous species of which 
have been described in an important memoir by M. von der 
Marck). 
Making allowances for insufficient data, we give the following 
as the results of these comparisons :— 
* F. J. Pictet, ‘ Paléontologie suisse,’ 1858, 1° série. Description des 
fossiles du terrain néocomien des Voirons. 
Ann. & Mag. N. Hist. Ser. 3. Vol. xvii. . 17 
