772 JOHN C. MERRIAM 
At Locality 5, a short distance (less than 100 feet) above No. 
4, fossils of the well-marked fauna to which Gabb gave the name 
Tejon are found in abundance, Cardium Coopert being the only 
really characteristic Martinez species associated with them. No 
localities showing more gradation between the Martinez and 
Tejon faunas than those here discussed have so far been discov- 
ered by the writer. 
Numerous other collections made between Localities 2 and 3 
and between 3 and 4 furnished gradations from one to the other, 
with some additional species not mentioned in the foregoing 
lists. 
In the following table there are placed together all of the 
species known to the writer from the strata between the Chico 
and the true Tejon near Martinez, along with those which have 
been collected elsewhere by Mr. Stanton, in beds of the same 
age. A study of this list shows clearly that the fauna is a unit, 
and that it is quite distinct from both the Chico and the Tejon, 
though it grades to some extent into the latter. 
The existence between the Chico and the Tejon of a fauna 
not belonging clearly to either group, was evidently not unknown 
to Gabb, and this fauna formed the real basis of his Martinez. 
Unfortunately the involved stratigraphy led him or his col- 
lectors into the error of supposing that certain Chico forms 
belonged in the same horizon with Martinez species, while the 
first error led to a second, viz., the belief that, since Chico forms 
were present in his Martinez fauna, the whole group might be 
found later to represent a subdivision of the Chico. As has 
been shown in the comparison of faunas, there can be little doubt 
that the Chico group is widely separated from what is here 
called Martinez. 
In considering the relations of the Martinez to the Tejon, it 
might be well to determine first what was intended in the origi- 
nal definition of the Tejon group and what it really is. The 
name was proposed by Gabb on faléontological grounds tor a set 
of rocks, supposed by him to be Cretaceous, but now generally 
regarded as Eocene, ‘‘most extensively developed in the vicinity 
