INTRODUCTION. xix 
Nature's work displayed in the teeming collections of minerals, fossils 
shells, and various forms of animal and vegetable creation? As yet' 
but few are the occasions when a single lecture or a demonstration 
is offered to a school or class brought to a particular gallery for that 
purpose. Before long, it may be hoped, the custom will be formed of 
instructing pupils from the very objects here presented to them rather 
than from written descriptions and engraved plates ; and with a 
clearer apprehension of the subjects so taught will grow a love for 
the study of them not so easily engendered by tuition from the 
book. 
EDWARD A. BOND, 
Principal Librarian. 
June 2nd, 1879. 
b 2 
