Bibliographical Notices. 131 



in 1830 on the so-called " transition series," he was further stimu- 

 lated in 1840 by the perusal of the 'Silurian System,' and his 

 labours assumed a definite plan. 



Those only who are conversant with the comitry, or will peruse 

 the volume, can form any idea of the zeal and energy requisite for 

 overcoming the difficulties of exploring this district, and the labour 

 and great pecuniary outlay necessary for accumulating the treasures 

 of this portion of the ancient Silurian fauna. Independently of his 

 own explorations over the whole district with a view of finding the 

 fossiliferous localities, whether in worked quarries, in ravuies, or on 

 the weathered surfaces of rocks, M. Barrande trained under his ovra 

 eye and practically instructed a number of intelligent workmen (fur- 

 nishing them with the necessary implements) for the more effectual 

 carrying out his researches at different points, and who became so 

 habituated to, and interested in, the employment, that scarcely the 

 fragment of an organism was ever lost. 



The follo\ving table will show the numerical result of species ob- 

 tained during these researches : — 



Genera. Species. 



Vertebrata Fishes 1 .... 1 



TTrilobites .... 35 .... 252 



Articulata < Cytherinidse . . 1 ... 25 to 30 



(_Various 4 . . . . 4 



'Cephalopods . . 10 270 to 280 



Pteropods 2 .... 25 to 30 



,, I Gasteropods . . ? .... 140 to 150 



MOLLUSCA <^ Brachiopods . . ? . . . . 180 to 200 



Acephala I 140 to 150 



Bryozoa 3 ... 22 to 25 



f Echinoderms . . .' .... 25 to 30 



\ Zoophytes ? .... 50 to 60 



From the the above it appears there are 1200 species of fossils 

 from the Bohemian basin, averaging about eighty mUes in length and 

 thirty in width, a sufficient dish for any Silurian gourmand. The 

 mere accumulation of such fossil treasures might be sufficient ; but 

 when the labour necessary for the determination of so manv species 

 is further considered, we must admire the industry of the author, and 

 we are well aware of the conscientious care with which the whole has 

 been effected. For (unlike some zoo-geologists, who centred in or 

 satisfied with the narrow limits of their own knowledge and locality, 

 not looking for determinations or comparisons elsewhere) M. Ba'r- 

 rande has, with the true spirit of a scientific man, entered into cor- 

 respondence with those naturalists who could assist him, and even 

 visited many localities, this country in particular, with a view of per- 

 sonally comparing the Bohemian fossils with the published types, as 

 well as with those not yet figured*. The present volume, with the 



* Particularly the collection of the Geological Survey, with the kind 

 co-operation of Prof. E. Forbes, and the important assistance of Mr. J. W. 

 Salter's practical knowledge, who has made the palaeozoic faima his esj>ecial 

 study. 



Radiata , 



