4!2 
PACIFIC EXPLORATION: C SCHUCHERT 
bottom through the eruption of rock material. What is the origin, 
however, of those that are arranged in linear series? Are they ranges of 
volcanoes that have Kkewise grown from the depths but are situated on 
lines of fracture in the lithosphere, or do they rest on the crests of great 
arches or foldings of the ocean bottoms? Equally important questions 
are: What is their geological history, and have they simultaneous or 
successive origins? So far as known, none of the smaller oceanic islands 
reveals fossils older than the later Tertiary, a condition that appears to 
be in harmony with the theory that the sum of their movements is 
negative and thus in keeping with the idea that the oceanic bottoms are 
subsiding areas. We have as yet little to show when they originated, and 
still on the basis of the periodically recurring diastrophism it would 
seem that none can be older than the Permian, a time of intense and 
world-wide crustal deformation. Others may have originated during 
the late Cretaceous crustal movements, and all may have again been 
reelevated and stirred into volcanic activity with the world-wide crustal 
readjustments that began in the Miocene and continued into late 
Pliocene time. 
The views just presented are those of most paleontologists, but there 
are geologists and zoogeographers who do not accept the idea of con- 
tinental fragmenting taking place on so large a scale as is here indicated. 
They hold firmly to the theory of the permanency of continents and 
ocean basins, believing that these positive and negative elements of the 
earth's surface have always retained the forms they now have. In their 
eyes, the physical evidence in the areas of fragmentation, and especially 
in the southern hemisphere, is not of a nature to compel the view that 
large lands formerly existed here, and they say, further, that there is 
no process in the mechanics of the earth known to them that would 
account for such down-breaking of the lithosphere. 
As for the ancient Kfe found in Australia, those who hold the above 
view say that we are still too ignorant of the world's organisms and their 
histories to conclude from them that their asylums were formerly con- 
nected with other land-masses, or they hold that the animals reached 
these places by accidental dispersal, through the air or by being rafted 
across the intervening water areas. Hence this conflict of views marks 
one of the greatest outstanding problems of geology and paleontology. 
The writer, however, is overwhelmed by the facts revealed in the geo- 
graphic distribution of ancient and modern animals, and is compelled 
to dissent from the rigid view of the permanency of continents. 
To sum up, in conclusion, we may say that the bottom of the Pacific 
Ocean in the region of greater Australasia seemingly became more and 
