80 Prof. Wagner on the Stinging Organs of the Meduse. 
the soil near the Waterfall at Habbie’s How. It weighs 8 
or 10 tons, and occupies a position about 1100 feet above the 
sea. No glacier, by the mere expansion of its mass, could 
earry this across 50 or 60 miles of low country, and lodge it 
where it lies. : 
Strata doubled over, and reversed.—Examples occur in the 
Alps of strata being doubled over, so that the newer rocks are 
found beneath the older. A remarkable specimen of this 
dislocated arrangement is described by Professor Hitchcok, 
as existing in the United States, and on a magnificent scale. 
The rocks consist of gneiss, mica-slate, tale, and clay-slate, 
with limestones and silurians. They extend from Canada 
along the east side of the Alleghanies, to Alabama, a distance 
of 1200 miles. He says—“ Along a large part of this distance 
a remarkable apparent inversion of the dip exhibits itself; so 
that the newer rocks appear to pass beneath the older ones ; 
and that, too, over a great width of surface. The effects of 
the extraordinary agency under consideration has not been 
simply to toss over the strata, so as to give them an inverted 
dip, but in general to produce a succession of folded axes, with 
a gentle slope and dip on the eastern side, and a high dip, or 
more frequently an inverted one, on their western side.” He 
thinks that all the strata between the Hudson and Connecticut 
rivers, a space of 50 miles in breadth, have undergone this re- 
plication. He admits, however, that some geologists doubt 
the fact, and consider the inversion apparent only ; but assum- 
ing its accuracy, he explains it, as Sir James Hall explained 
the foldings in the Lammermuir Hills, by supposing that the 
strata were forced to double over from being compressed 
edgeways. OC. Maclaren, Esq. F.RS.E. &e. 
On the supposed Stinging Organs of Meduse, and the occur- 
rence of peculiar Structures in Invertebrate Animals, which 
seem to constitute a new class of Organs of Motion. By Pro- 
fessor Rupotew Wacner of Gottingen. 
Ir is well known that it has not yet been ascertained whe- 
ther the stinging or burning power of Meduse is to be ascribed 
to a corrosive liquid, or to a mechanical injury. I think 
