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between the coast and the metropolis of this group of shells, calls for 
some explanation and remarks on the geographical range, and the 
means of distribution of such slow-moving creatures. 
Undoubtedly in the early history of the continent, it has been ele- 
vated and submerged several times above and below the sea level, 
before the land assumed its present state or condition. The great 
abundance of marine fossils in the various stratas of rocks in every 
part of the country, inland as well as along the coast, and in the low 
valleys as well as on the high mountains, confirm this statement. 
Perhaps, after many hundreds of centuries had passed, and dur- 
ing the miocene or about the middle of tertiary times, the continent 
became comparatively quiet, and when the great lake system of the 
interior had become well established, and dense forests and rank 
vegetation had become well developed, and served as food for the great 
herbiverous creatures of that time, whose fossil remains are found in 
almost every part of the continent, whose bodies became, in turn, the 
food of the huge carniverous amphibians that lived in the lakes and 
low marshy land at that time, and were probably the terror of their 
day, and whose fossil remains are the wonder of men at the present 
time. 
It is quite possible that land shells and probably [elix strigosa, 
or its progenitor of large size, may have occupied the higher and dryer 
areas of the land, as it does today, and became widely distributed by 
the floods and drainage system of that time, Santa Catalina Island, 
with the other islands of the Santa Barbara group, were probably 
high landmarks of a broad range of mountains, at that time, and ex- 
tended many miles in a northerly and southerly direction, and probably 
spread out many miles beyond San Nicolas, the outermost island of 
the Santa Barbara group. 
Perhaps, during the latter part of miocene times, this colony of 
the strigosa group and the other land shells that are peculiar to these 
islands today, occupied high areas on these mountains. At the eloge 
of the miocene period great volcanic disturbances occurred again, 
when this Santa Barbara range, as it may be ealled, went down below 
the sea, leaving the eight islands standing above the turbulent waters. 
as monuments or tombstones to mark its burial place, where these 
stranded colonies of land shells have continued to exist but have be- 
come somewhat modified in form. Fossil land shells of the present 
living forms, indicate considerable age and seem to support these 
assertions and suppositions. 
About the time that this western range of mountains became 
submerged, another and perhaps the last general elevation of the 
continent took place, when a hundred voleanoes on its western slope, 
