PEEFACE. 



THE Author having had frequent occasions for referring to Comparative 

 Anatomy during the progress of his publications on the Nervous System, he con- 

 ceived that representations of his dissections might interest many, and especially 

 assist those who were about to enter upon similar pursuits. But, on so compre- 

 hensive a subject, it became difficult to determine upon an arrangement that 

 would make a work concise and useful. After much consideration, it appeared 

 probable that this intention would be in a great measure answered by selecting 

 such examples as would explain the scheme on which the nervous system is 

 generally founded; for thus its practical investigation would be facilitated, and the 

 extension of knowledge promoted in the best and most efficient manner. 



It is desirable that researches by actual dissection should be encouraged as 

 much as possible, as thus only can the prospective advantages of science be 

 consulted. If books be entirely confided in, all improvement must stop. These 

 ought, therefore, to be esteemed as mere helps towards that perfection, which 

 can only be approached by the active perseverance of individuals through pro- 

 'gressive ages. If the laborious investigations, hitherto instituted, have produced 



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