10 Joe CSB RAUNGINIEDR: 
with.” ‘Oyster shells” were obtained in a stratum of bluish sand, 
and a stratum of blue clay containing numerous “clam shells”’ is said 
to have been bored through about two miles north of Alviso. The 
finding of these marine deposits seems to show that the materials 
in the valley bottom are not of land origin. ‘The deposits referred 
to might be either preglacial or postglacial without interfering with 
the theory of the elevation of the coast during the glacial epoch. In 
every instance, however, these marine shells have been found so near 
the present Bay of San Francisco that I am disposed to believe that 
the deposits containing them belong to the late history of the Bay and 
not to the more remote period. 
Résumé.—The theory of the postglacial age of the Golden Gate 
does not appear tenable. ‘The watershed at Madrone in the Santa 
Clara Valley between Coyote Creek and Pajaro River is not the 
lowest one between the Bay of San Francisco and the Pacific; the one 
at Colma is 155 feet lower, and another in Elk Valley is also 155 feet 
lower. The mingling of the fish faunas of streams flowing into the 
Bay of Monterey with those of streams entering the Bay of San Fran- 
cisco is explained by the fact that Coyote Creek, descending into the 
Santa Clara Valley from the Mount Hamilton range at the crest of 
the watershed between the San Francisco Bay and the Bay of Mont- 
erey, formed an alluvial cone and swung from side to side, emptying 
part of the time into the Pajaro and part of the time into the Coyote. 
The passage of fishes between the various streams entering the Bay 
of San Francisco must have taken place at a time when the coast 
stood enough higher than it does at present to have emptied the Bay 
of San Francisco, and thus to have permitted fishes to descend from 
the Sacramento and ascend the Coyote and other streams without 
entering salt water. ‘This same elevation would permit the passage 
of fishes between streams entering the Bay of Monterey. 
It is believed that the elevation that united these streams occurred 
during the glacial epoch, and that it was the larger run-off of waters 
of that epoch that built up the alluvial cone where the Coyote debouches 
on the flat floor of the Santa Clara Valley. 
