734 THE JOURNAL OF GEOLOGY. 
The study of the cliffs has brought us back to this old hypoth- 
esis with renewed assurance of its innate probability. 
In considering this question it is important to have clearly 
in mind the relations sustained by the ‘East Alps” (that 
portion of the Alps lying to theseast of the Whine) onthe 
one hand, and by the Freiburg Alps to the west of Lake Thun 
on the other to our cliff masses. (Compare accompanying 
map.) The East Alps bound the cliff zone on the east as 
do the Alps of Freiburg on the west. Both the East Alps 
and the Alps of Freiburg have long been known to contain 
a Mesozoic rock series facially quite distinct from those 
of the normal Swiss mesozoic, so that the term ‘ Helvetian 
(Swiss) series,’ “East Alpine series” and ‘Freiburg series” 
have been used to distinguish the three. Since the time of 
Brunner’s discovery of Avicula contorta, a characteristic East 
Alpine upper Trias form, in the Alps of Freiburg (Stockholm) 
it has been repeatedly pointed out that there are numerous fea- 
tures of resemblance between the strata of these two territories 
lying at either extremity of our cliff zone. Realizing the impor- 
tance of establishing this point and the relations of the cliffs to 
the whole, I undertook to make a tabulation of the strata and 
fossils of the Trias, Jura and lower Cretaceous (all occurring in 
the elitts) and exotic sblocks)) on (a)\sthe ta ast ilps ;ca(2))mebe 
cliffs and exotic blocks, and (3) the Alps of Freiburg. The 
result of this comparison has shown that the strata of all three 
have essentially the same facial development, and might belong 
therefore to the same basin of deposit. (For the geographic 
relations of these regions see map.) The importance of this 
point for the understanding of the cliffs can hardly be over- 
estimated. It shows us that the basin of deposit of the East 
Alpine series was not confined to the east of the Rhine, but 
extended, or at least repeated itself, far to the west of it along 
the north border of the Alps; it shows us further that the cliff 
zone stretches between the East Alps and Freiburg Alps as the 
remnant of a once more or less continuous deposit connecting 
the two; and it leads us to suspect that on the same basis of 
unity whatever greater movements have taken place in the cliff 
