Introduction. 
’ Vll 
Eastern Agricultural College for the great help he has given me 
in the concluding part <£>f this volume; had it not been for his 
final efforts it could not have been now produced. 
To Mr. C. O. Waterhouse of the British Museum I am still 
more indebted for his careful revision of the proofs, and his 
usual valuable and kindly suggestions. Mr. Robert iSTewstead of 
the School of Tropical Medicine at Liverpool has placed his 
types at my disposal, and has given me much information and 
help generally. 
The photographs as before have been taken by Mr. F. Edenden 
of Wye, and the drawings have been prepared by Miss C. Beard 
and Mr. H. F. Carter. 
Wye Court, Wye. 
March 20, 1910. 
FRED. Y. THEOBALD. 
