228 W.M. Gabb on the Cretaceous rocks of California. 
nized and described 280 species, besides about fifty species not 
yet described but of which we have sufficient material for publi- 
cation, and about 30 or 40 species, the existence of which is in- 
dicated by fragments too imperfect for description. Of these 
species 107 are found in Division B. Of these 107, 84 are, so 
far as known, peculiar to this group, and 16 are found in com 
mon in undoubted members of both divisions, while 7 more are 
found in the intermediate beds associated with a nearly equal 
number of representatives of the lower group. Thus the two 
groups are connected by a passage of nearly one-fifth of all the 
species found in the upper member, 
The following analysis will prove the above statements more 
clearly. 
Of the 107 species of fossils found in Division B, 44 are found 
at Clayton, 67 at Tejon, 54 at Martinez, 22 at San Diego, 18 
near Griswold’s, and 7 near New Idria, It is not intended to 
be understood that these are all of the species found at these lo- 
calities ; but that, up to the present time, these are all that have 
been identified or described. Future work will undoubtedly 
change the above figures, 
Of the species found at the above localities, 50 are peculiar 
to one or another locality; 29 are found at two localities only, 
14 at three localities, and 14 at four localities or more 
As I have stated above, 16 species found in the upper mem 
ber also extend into the older group, Division A. In addition 
to this, at the locality near Lower Lake Village, Lake county, 
besides Several species encountered for the first time, I found 15 
species in the same bed, within a superficial area of two feet 
Sees, 3 were previously known to be common to the uppet 
and lower division, Besides these 8, 7 of them were common 
to this locality, and localities of division B, and the remaining 
5 were, before this di 
> wer is discovery, considered peculiar to the lowe 
member. One of these 5 is found in the Mississippi Valley, @ 
the “Ripley Group,” and another belongs to a peculiarly Cret# 
ceous genus, 
, 78 to the species found at the several typical localities, indepe®” 
Gest. Shame . other, and which would a to show their indi 
ae telations to the older formation without corroborative 
ie sees ertan has 10 species in common with Division A, 
gjon has 7, and Martinez 11. With the Lower Lake bed, Clay” 
ton has 5 speeies in common, Tejon d Mart: 
1, 
: 5, an inez 6. 
In glancing over Mr. Conrad’s ‘check list” I find that out of 
the 107 species found in his “Older Eocene of California,” b¢ 
