TO 



THOMAS HENRY HUXLEY, LL.D., F.R.S., 



TO WHOM THE AUTHOR IS INDEBTED FOR MANY MARKS OF PERSONAL KINDNESS 



AND WORDS OF ENCOURAGEMENT 



DURING THE PREPARATION OF THIS TREATISE; 



AND TO WHOSE TEACHING IN THE LECTURE-ROOM AND LABORATORY HE IS CHIEFLY 



BEHOLDEN FOR HIS QUALIFICATION 



TO ENTER AS A HUMBLE LABOURER UPON THE ARENA OF SCIENTIFIC INVESTIGATION 



THIS 'manual of the INFUSORIA' IS GRATEFULLY 



