VI INTRODUCTION. 



American species described by Mr. Thomas Say in the * Trans- 

 actions of the Academy of Natural Sciences of Philadelphia ; ' 

 also by myself, in Griffith's translation of Cuvier's ' Animal 

 Kingdom.' 



To give some idea of the extent of the collection, I may 

 state that M. Brandt, in his Memoirs in the 'Bulletin de 

 1'Academie Imperialedes Sciences de St. Petersbourg,' the last 

 general work on the subject, indicates 16 ascertained and 9 

 doubtful species of Chilopoda, and 117 ascertained and 16 

 doubtful species of Chilognatha : the Museum collection con- 

 tains 94 species of the former and 75 of the latter order, the 

 majority of which appear to have been unknown to that author. 



JOHN EDWARD GRAY. 



British Museum, 



June 1, 1844. 





