NOTE ON THE ILLUSTRATIONS. 



WITH the exception of figs. 5 and 6 in the text, which 

 have been re-drawn, all the illustrations in this volume are 

 photographic reproductions of original drawings by the 

 authors the coloured plates and the illustrations in the text, 

 by the half-tone process ; the uncoloured plates (the frontis- 

 piece excepted), by collotype. 



The Editor has ai-ranged the figures on the plates and in 

 the text, and has strengthened the outlines and more impor- 

 tant details which were too faint for the camera. In all other 

 respects the figures are exact reproductions of the authors' 

 drawings, a result only attainable by photography. Owing, 

 however, to the paper on which some of the figures in the 

 collotype plates were drawn having changed colour with age, 

 the ground is in some cases too dark, and in Plates XVII 

 and XVIII is not uniform in shade. 



Plates I, y, VII, XI, XV, and XVI are from drawings by 

 Mr. Alder, and the figures are of the same size as drawn by 

 him. The rest, and all the text illustrations, are from 

 drawings by Mr. Hancock, and nearly all these are reduced 

 in size in various proportions. 



JOHN HOPKINSON. 



WEETWOOD, WATFORD, 



27 th March, 1905. 



