Review of Recent Geological Literature. 197 
to the same horizon as certain parts of the Old Red (Devonian) sandstone 
of Scotland. It is well known that the Old Red of Scotland aud the Devon¬ 
shire formations of England present such different characteristics alike 
petrographic and paleontologic, that in Great Britain no synchronism 
whatever between these deposits can be affirmed. Bud, M. Lohest assures 
us, this synchronism is now rendered possible by the discovery in Belgium 
of an ichthyic fauna comparable to that of the Old Red mingled with a 
molliiscan fauna analogous to that 1 ound in Devonshire. 
Our author also discusses the mooted question whether the Old Red 
sandstones were deposited in salt water or in fresh. “With good reason he 
affirms that the presence in fresh water of our modern ganoids whose 
affinities with their paleozoic predecessors are so close, does hot neces¬ 
sarily imply for the former an identical habitat. All our fresh-water 
fauna had probably, more or less remotely, an origin marine.” But M. 
Lohest argues that the correlation of the different strata mentioned above 
by which correlation mollusca, certainly marine, are associated with those 
ancient ganoids makes a fresh water habitat for the latter extremely im¬ 
probable. 
By his comparative study of the British and Belgic Devonian, M. Lohest 
is led to propose an explanation of the want of concordance in certain types 
of fishes occupying successive deposits in the Belgian formation. 
He suggests that to assume an alternation of deposits as between Scot¬ 
land and Belgium explains the difficulty. The Scotch formations bio¬ 
logically fill the hiatus between the older and later deposits on the conti¬ 
nent; as if by successive changes in level the ganoid and dipnoid fauna 
had migrated first from Belgium to Scotland and then back again to 
Belgium. 
A second brochure by the same author, (M. Lohest,) issued at the same 
time and place as the memoir just considered, announces the discovery of 
what is esteemed “the most ancient amphibian known” to science. A 
fragmentary skeleton from the upper Devonian is figured and briefly 
described. 
The Iron Ores of the Penokee-Oogebic Series of Michigan and Wisconsin 
—With Plate. By C. R. Van Hise. (From the American Journal of 
Science for January, 1889.) The author treats first of the series of rocks 
in which the iron ores occur—a series running across the country in a- 
direction approximately east and west, from the vicinity of Numakagon 
lake, Wis., to Gogebic lake, Mich., a distance of more than 80 miles. The 
series lia3 been tilted to the north at an angle of 60 3 to 80 = , rests on a com¬ 
plex of granites, gneiss and green schists, and is overlain by eruptives of 
the Keweenaw series. There are four members to the Penokee-Gogebic 
series,— first, cherty limestone,— second , feldspathic quartz-slate,— third, 
non-fragmental sediments 800 feet thick and known as the iron-bearing 
member,— fourth, a series of greywackes, greywacke-slates, and mica- 
schists and slates, in the aggregate several times thicker than the other 
three members combined. 
The iron-bearing formation is traversed by dykes of greenstones or other 
