INTRODUCTION. V 



In conclusion, our grateful thanks are tendered to Dr R. 

 Bridges of Philadelphia, whose valuable assistance has largely- 

 contributed to the accuracy and usefulness of this volume ; 

 also to Dr H. M'Murtrie, and his excellent translation of 

 Cuvier, which leaves nothing further to be desired, either by 

 the teacher or the pupil. 



T. W. 





