viii PREFACE 



of several Vertebrates forms as good a training as any for 

 beginners more especially in the case of medical students. 

 I am indebted to Mr. H. Spencer Harrison, B.Sc., 

 Demonstrator of Biology in this College, for much assistance 

 in testing and improving the practical instructions, as well 

 as for various suggestions and for help while the work was 

 passing through the press. The new figures were redrawn 

 from the originals by Mr. M. P. Parker. 



W. N. PARKER. 

 UNIVERSITY COLLEGE, CARDIFF, 

 November , 1899. 



PREFACE TO SECOND EDITION 



AFTER a practical experience of this book in my classes 

 for the last eight years, I have tried to increase its useful- 

 ness by slightly extending some parts and by making 

 various minor modifications throughout. Short accounts 

 are given of Monocystis, as an example of a sporozoan 

 parasite, and of Nereis, for comparison with the earthworm ; 

 while Bougainvillea is replaced by Obelia, and several 

 additional figures are inserted. 



W. N. PARKER. 



November ; 1907. 



