1891.] Geology and Paleontology. 567 
‘In the Alps there exists, as has frequently been pointed out by those 
who have preceded me, a great group of crystalline schists, the bulk 
of which must be metamorphosed sedimentary deposits. This group 
can be traced, practically without a break, from one end of the chain 
to the other. These schists certainly.overlie, sometimes it would seem 
unconformably, another series of gneisses and schists, generally coarser 
in texture. These seem to be divisible into two groups, differing in 
lithological characters, of which the upper, though sometimes well 
eveloped, is not seldom wanting; so that instead of the gradual 
transition from it to the first-nafed group, which can sometimes be 
observed, we find the latter resting with marked discordance upon 
some part of the lower series. 
“The oldest unaltered rocks in the Alps generally belong to the 
lowest part of the Mesozoic system, Jurassic or Triassic (possibly 
sometimes Permian), but in certain districts not inconsiderable deposits 
of Carboniferous age (quite disconnected from the last named) occur, 
and in the northeastern Alps Paleozoic rocks of yet earlier date have 
been identified. All these are practically unaltered, An exceptionally 
wide experience enables me to affirm, without fear of contradiction, 
that, in case of any large mass which would be referred without hesi- 
tation to the Jurassic, Triassic, or Carboniferous group, there will not 
be found, however great may have been the mechanical disturbances 
~ which it has undergone, any transition exhibited by it into one of the 
normal gneisses or schists ; at most a microfoliation has been developed 
or a superficial resemblance set up. The crystalline schists also do not 
exhibit, as a rule, any tendency to pass into ordinary sedimentary 
rocks. Appearances suggestive of this transition are found on closer 
examination to be due either to pulverization of the rocks by pressure, 
or to the inclusion of a later series by folding or faulting. 
“ But while there can be no doubt of the general truth of this state- 
ment, it has recently been asserted that in certain districts of the Alps 
there is a passage from Jurassic rocks into truly crystalline noah 
while in others fossils of that age occur together with garnet, mr 
and minerals resembłing staurolite, in schists which cannot be distin- 
guished from certain members of the above-named eer If B x 
assertion be correct, it must follow (1) that the Alps exhibit true TERU 
and (2) that, 
Masmuch as these are undistinguishable fro! 
_ &raphical evidence can be proved to be very mu 
Mesozoic rocks, a schist, like a granite or a dolerite, 
almost any geological epoch. 
might belong to 
M 
