164 Conglomerates in Gneissic Terranes — A. Winchell. 
conglomerate, is so different that I am unwilling to admit that 
they can both belong to one series and have been subjected to 
similar conditions/’ He mentions also, the absence of any 
passage from one to the other; the identification of both series 
with others known to be discordant to one another, and the 
analogy of other similar foldings in, of newer rocks, so as to 
produce on the surface the effect of a true sequence. The ex¬ 
planation was admitted however, to be purely hypothetical. In 
the discussion of professor Hughes’ speculation before the Geo¬ 
logical Society, every one admitted the possibility of an infold¬ 
ing, and could cite cases in illustration. Mr. Bauerman thought 
the explanation offered of the Obermittweida occurrence was 
probably the true one. Dr. Geikie mentioned a case of Cam¬ 
brian conglomerates in Scotland, of which he was reminded, 
where there is u a passage from crushed conglomerates and sand¬ 
stones into mica-schist.” 
The Obermittweida conglomerate has been discussed also 
microscopically by professor T. S. Bonney.* The matrix of the 
conglomerate, though clearly fragmental in origin, suggests 
that “a certain amount of metamorphism in situ has taken 
place. * * * The gneiss has a superficial resemblance 
to this matrix, but is rather more distinctly micaceous.” The 
gneiss is quite characteristic and resembles one of the older 
Alpine gneisses. The matrix does not give evidence of much 
squeezing. It has essentially the constitution of gneiss, but at 
the same time, “the fragmental character of the rock is indubi¬ 
table.” He does not incline to regard it as post-Archaean, but 
it is probably long subsequent to the gneiss, and its appearance 
of consecutiveness is probably illusory. 
Such an explanation, 1 repeat, will not apply to the case of 
the Saganaga conglomerate, where the matrix is absolutely of 
the same character as the gneiss of the contiguous region. 
The German geologists, as would be expected, endeavor gen¬ 
erally to explain the Obermittweida conglomerate without 
recognizing its real fragmental character. Yon Hauer referred 
to it as only something like a conglomerate. J. Lehmann says 
the pebbles cannot be regarded as rolled stones, notwithstanding 
the complete rounding and smoothness of some of them.'* Roth 
does not admit the pebbles were included rolled fragments, but 
* Quar. Jour. Geol.Soc ., xliv, Feb. 1, 1888, pp. 25-31. 
