P E E F A C E. 



I HAVE again been indebted to Captain Savile G. Eeid for his 

 assistance in the preparation of the present volume, and for 

 the additions which he has made to Mr. Gates' original MSS. The 

 valuable collections -which the Museum has received during the 

 past two years have greatty added to the importance of the 

 present volume. The donations of Mr. W. Eadcliffe Saunders and 

 Mr. C. B. Eickett have been especially valuable. 



E. RAY LANKESTER, 



Director. 



British Museum (Natural History), 

 February 22, 1905. 



