Vlll 



PREFACE. 



subjects dealt with have appeared since the publication of our current zoological text- 

 books, I append a bibliography of them, together with certain classical monographs 

 indispensable to those desirous of extending either their own knowledge, or that of their 

 fellows, in the matter concerned. 



The titles of the above-named works are arranged under heads and numbered for 

 purposes of reference in the text. 



In preparing this work, it has been my good fortune to have had the counsel of 

 Professor HUXLEY, and I have to acknowledge my indebtedness to Professors T. J. 

 PABKEB and E. K. LANKESTEK, and to Mr. F. 0. BOWEK. My friend Mr. M. M. TEBBEBO 

 and certain of my pupils have rendered me welcome aid in the matter of cutting 

 sections, and my thanks are due to my lithographer, Mr. M. P. PABKEB, for the able 

 manner in which he has carried out my wishes. 



NORMAL SCHOOL OF SCIENCE AND ROYAL SCHOOL OF MINES, 

 SOUTH KENSINGTON, February, 1885. 



GEO. BOND HOWES. 



