142 



THE GEOLOGIST. 



FOREIGN CORRESPONDENCE. 



On the Sihuricm " Colonies " of Bohemia. By Me. M. V. Lipoid. 



Certain strata of greenstones, graptolite -shales, and concretionary 

 limestones, petrographically and palteontologicaUy analogous to M. 

 Barrande's "superior Silurian etage E" (" Litten-strata" of the 

 geologists of the Vienna Imperial Institute), but appearing in isolated 

 lenticular masses between the slates and quartzite-sandstones of his 

 " Lower Silurian etage D," have been pronounced by M. Barrande 

 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 immigrated 

 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 Director 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 MM. Haidinger and Krejcy,* south of Prague, 

 near Gros-kuckel, lying within the slates and quartzite-sandstones 

 (" Konigshof " and " Kossow" strata of the Vienna geologists) of 

 M. Barrande's "etage D," division D 5 , and re-examined with 

 " 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 Silurians, 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 M. Barrande lias delivered to the Geol. Soc. of France (meet- 

 ing of. I une Itli, 1S(U>) a paper on " Colonies," and read an abstract of it concern- 

 in- the colonies « Haidinger" and " Krejcy." (Sec Bulletin de la Societe Geolo- 

 giqne de France, 2e serie, t, xvii., p. 302.) 



