200 THE CANADIAN NATURALIST. [Vol. vi. 



Bracliiopods, 



Atryi^a niarginalis, Dalm. 



Cijrtia trapezoidalis, Dalm. 



Lei^tcena sericea, Sow. 



firmsversaUs, Dalm. 



Ortliis elegantida, Dalm. 



hyhrida, Sow. 



StfOjjhomena depresscij Sow. 



pecten, Linn. 



Graptolites. 



Graptolites convolutiis, His. 



furncidatus, Barr. 



Diplograpsus pahneus, Barr. 



Rastrifes Linncei, Barr. 



RetioUtes Geinitziamis, Barr. 

 Corals. 



Favosites alveolaris, Blainv. 



Holy sites catenularius, Linn. 



Heliolites interstinctus, Wahl. 



tuhulatuSj Lonsdale. 



Of the above twenty species thus enumerated as common to 

 the Upper Silurians of Bohemia and the Lower Silurians of 

 Britain, four species are found in the Llandeilo, all (with the 

 doubtful exception of 7?efto/t7es Geinitziainis) Sire found in the 

 Caradoc, and fifteen species occur in the Llandovery rocks of the 

 latter country. Not one of these species, on the other hand, is 

 found in the corresponding rocks of Bohemia, namely in the 

 second fauna. These species, therefore, go to show that " the 

 elements of the third fauna of Bohemia, which are represented in 

 the colonial fauna, existed in notable numbers in a foreign coun- 

 try, at a time when the second fauna still predominated in the 

 Silurian basin of Bohemia. These species thus establish an 

 indirect connexion between the second fauna of Britain and the 

 colonies of Bohemia. 



VI. General Conclusions. 



As to the general conclusions which may be deduced from the 

 whole of the above facts, it will be sufficient to give briefly the 

 series of propositions laid down by M. Barrande, merely remark- 

 ing that these conclusions are in the main warranted by the facts, 

 and that any subsequent modifications are not likely to affect their 

 general tenor. 



