The Intumescens Fauna. — Clarke. 105 
middle Upper Devonian of Enrope, than of its marine fauna. 
Nevertheless, it ma}' be observed that the fauna contains an un- 
described species of Goniatites not far from G. miiensteri and an 
Entomis allied to ^. {Cypridina) serratostriatn,, both of which 
characterize the upper zones of the Devonian in Westphalia. 
In conclusion it maj' be said that we have in the Upper Devonian 
of western New York, at the base, in the Tully limestone, a 
sparsel}- represented time-equivalent of the C uboides zone ( brach- 
iopod facies); this is followed by an abundant development of a 
normal Intumescens fauna, involved in shales which bear to a 
greater or less extent a fauna of a local or indigenous character. 
This Intumescens fauna or cephalopod facies of the lower Upper 
Devonian, includes certain elements at a maximum development 
( Cardiola retrostriata, coniferous woods) which in the European 
succession, frequently occup}' distinct horizons below and above 
the normal horizon of the Intumescens zone. 
ON A PECULIAR FORM OF METALLIC IRON FOUND 
IN HURONIAN QUARTZITE, ON THE NORTH 
SHORE OF ST. JOSEPH ISLAND, LAKE 
HURON, ONTARIO.* 
By G. Christian Hoffman. F. Inst. Clieiii., Chemist and Mineralogist to the 
Geological and Natural History Survey of Canada. 
In the course of examining some surface specimens of quartz- 
ite^ from the north shore — fifth concession, back of Campement 
d'Ours — of St. Joseph Island, it was observed that certain faces, 
apparentl}-^ fissure surfaces, of the same, were coated with a thin 
deposit of dark reddish-brown limonite through which was dissem- 
inated numerous metallic looking spherules, thereby imparting to 
it an oolitic structure. In the specimen which best showed its 
mode of occurrence, this deposit formed a layer, on one face, of 
from one to one and a-half millimetre in thickness, and this, judg- 
ing from the appearance of the exposed surface of the same, 
which showed indications of having l)een a contact surface, may 
perhaps be fairly assumed to represent the diameter of the origi- 
nal fissure. Running parallel to and in direct communication 
with the latter was a gouge-shaped groove measuring where it 
■*From the Transactions of the Royal Society of Canada, vol. viii, 1801. 
'A greyish, in parts greenish and brownish coloured quartzite. with 
here and there an inclusion of white vitreous quartz, and red and black- 
ish or brownish black jasper. 
