IV PREFACE. 
a carefully selected number of the types of the larger groups. But 
the exhibition of very complete series, supplemented by models or 
figures, to illustrate the remarkable life-history of some of these 
animals, also of specimens of the Worms which possess a special 
interest from their relation to man, render this Gallery particularly 
instructive to the student. 
This guide has been prepared by Mr. E. A, Smith, Mr. F. J. 
Bell, and Mr. R. Kirkpatrick, who have special charge of the 
collections described. 
In conclusion, thanks are due to Messrs. A. & C. Black, Messrs. 
F. Warne & Co., Messrs. Macmillan & Co., Crosby Lockwood & 
Son, and the Linnean Society for kindly allowing the use of cliches 
from illustrations in various works published by them. 
B. RAY LANKESTER. 
