142 
THE GEOLOGIST. 
FOREIGN CORRESPONDENCE. 
0)1 tJiG Silurian " Colonies " of Bohemia. By Mr. M. Y. Lipold. 
Certain strata of gTeenstones, gi'aptolite -shales, and concretionaiy 
limestones, petrograpliically and paleeontologically analogous to M. 
Barrande's "superior Silurian etage E" (" Litten-strata" of the 
geologists of the Vienna Imperiallnstitute), but appearing in isolated 
lenticular masses between the slates and quartzite-sandstones of his 
" Lower Silurian etage D," have been pronounced by M. Ban^ande 
to be " colonies," the fauna of which, already existing in a distant 
sea at the period when the strata of the " etage D" were forming on 
the present Silurian region of Central Bohemia, had immigTated 
thither under favourable conditions, and had subsequently dis- 
appeared, together with these conditions, to reappear again and come 
to its full development after the strata of " etage D" had been com- 
pletely deposited at the bottom of the Silurian sea. Prof. Krejcy, of 
Prague, having co-operated as a volunteer with the geologists of the 
Imperial Institute in the survey of the environs of Prague and 
Beraun during the summer of 1859, has made some objection to the 
explanation of the above-mentioned facts as given by M. Barrande, 
as, according to his views, they could be very well accounted for by 
upheaval and disturbances which had affected the upper and lower 
strata of Bohemia. M. Barrande, having protested against this 
assertion, M. Lipoid was entrusted by Dii'ector Haidinger with the 
close examination of one or more of M. Barrande's " colonies." The 
results of this examination, made in the summer of 1860, are given 
in the present report. M. Lipoid closely examined the " colonies" 
named in honour of MI. Haidinger and Krejcy,* south of Prag-ue, 
near Gros-kuckel, lying within the slates and quartzite-sandstones 
(" Konigshof " and " Kossow" strata of the Vienna geologists) of 
M. BaiTande's "etage D," division D^, and re-examined ^vith 
" scrupulous" attention Prof Krejcy's survey on the south margin of 
the Upper Silurians, proceeding south-westward from Gross Kuckel 
to the environs of Litten, along a line of about fourteen English 
miles in length. The facts stated by this survey are traced on two 
geological maps, and on a series of sections. They show the 
"Konigshof" and " Kossow strata" on the south margin of the 
Upper Silui'ians, together with the " Litten strata," to have under- 
gone repeated foldings and dislocations. Two such foldings and 
dislocations of the "Konigshof" and " Kossow-strata," extending 
* Since this time BaiTande has delivered to the Geol. Soc. of France (meet- 
ing of June 4th, I860) a paper on " Colonies," and read an abstract of it concern- 
ing the colonies " Haidinger" and " Krejcy." (See Bulletin de la Societe Geolo- 
gique dc France, 2c serie, t. xvii., p. 302.) 
