FACTS AND OBSERVATIONS. xxxi 



Instead of only four Bohemian orders, as in Russia, England contains nine orders, Norway 

 eight, Sweden and Ireland each seven together, in each country, with a plentiful supply of species. 



If we are to believe that the Bohemian sea overspread a large portion of Europe in the early 

 stages of the Silurian epoch, it shows the same amplitude and magnificence of design which is 

 exhibited by the Silurian areas of North-east America, whether we regard their more complete 

 exhibition in the valleys of the Mississippi and the St. Lawrence, or the vast expanse of Upper 

 Silurian strata in Northern and Arctic America, where it-is, meat pfe&ftbte4htct the Lower Silurian 

 stages aevor existed. ^~ <* 2 -^ fl 



Communities. The natural history of the communities of this epoch has not as yet received 

 due attention. Professor M'Coy and Mr. Billings have given several interesting skeleton lists of 

 this kind, but they have gone no further. Neither analysis nor conclusions belonged to their 

 immediate duties. Instructive instances of these groupings lie ready in every land. Some of the 

 earliest life with which we are acquainted is found to be in societies, consisting of individuals drawn 

 together by their instincts, and retained for a longer or shorter time by a sense of ease and safety ; 

 but no mollusk is absolutely fixed to any one community. Removals are common, andt hey are 

 called acts of migration or of recurrence. What species or genera can or cannot coexist in the 

 same community, the incompatible^ and compatibles, from powers, wants, or external conditions, 

 is only partially ascertained. 



The bed e. 2 of the Bohemian stage E possesses unusual interest from the number, diversity, 

 and rank of the life it contains. 



Of the sixteen * subdivisions established in this basin by M. Barrande, that which he has 

 named E. e. 2 (the seventh from the bottom) is by far the most prolific. Of the 2093 marine 

 forms held by the whole basin, nearly one-half (921) are in this bed, of no great thickness (150 

 feet ?), and principally within a space of fifteen miles by seven. They evidently form one society ; 

 for there are no barriers between different parts of the subdivision, and there never were any. 



About Kozorz and Lochkov, and for seven miles around these villages, the rocks are the most 

 crowded (see Map), and especially by Cephalopoda, distributed with some irregularity : the Bra- 

 chiopoda often at Dlauha Hora, Lodenitz, Luzetz, &c. ; the Gasteropoda at Lochkov, Karlstein, 

 Dlauha Hora, Dvoretz, &c. ; the Dimyaria at Dvoretz, Karlstein, &c. ; and so on, still on the same 

 horizon, E. e. 2. 



The Cephalopoda and Gasteropoda are in numbers especially astonishing when we remember 

 that each species brings its thousands or millions of highly endowed individuals. These two orders 

 give us 714 species, or about four-fifths of the organic remains of this bed (E. e. 2). The parishes 

 of Lochkov and Kozorz seem to be the headquarters of the Cephalopoda. They have seventy -five 

 species in common ; while Lochkov has 220, and Kozorz 102, exclusively its own. 



The following Table (Q) gives, in a condensed form, the known population of fauna E. e. 2 

 (numerically) . 2 



C- L- ; * Fauna D, 5 ; fauna E,>L; fauna F, 2 ; fauna G, 3 ; fauna H, g ; = 16. 



