INTRODUCTION. ix 



is that adopted by Professor Huxle}^ Professor Eolleston, 

 and others, of describing completely a single included spe- 

 cies ; but this method seems more suited for students than 

 for a mixed company, such as have visited our Institution 

 since October, 1861, during which period the admissions to 

 the Liverpool Museum have exceeded 5,000,000. 



The following is the plan of arrangement adopted in con- 

 nexion with each group. Wherever circumstances permit, 

 the plan for each^ group includes (1) A printed schedule.' 

 (2) Exotic species. (3) British representatives. (4) The 

 printed tablet. (5) Earliest fossils. (6) Diagrams and other 

 illustrations. (7) Species and varieties on a more extended 

 scale. 



(1) The schedule, of which an example follows, is printed 

 in large type, and is attached, conspicuously, to the drawer. 



Group 222. 

 Sub-Kingdom - Anmilosa, Skeleton external, ringed. 

 Province - Arthropoda, Limbs jointed. 

 Class - Irisecta, Legs six. 



Sub-Class - Metahola, Transformations complete. 

 Order - Lepidoptera, Wings with scales. 

 Sub-order - Rhopalocera, Horns clubbed at the apex. 

 Family - Papiliomdce, Middle nerve of fore-wing 



four-branched. 



The next sub-division appears, not on the schedule, but 

 on the printed tablet, as the distinctive title of the 222nd 

 group. The following is a copy of the tablet pertaining to 

 the 222nd group : — 



" Genus Ornithoptera and allies. 



Bird-winged Butterflies. 

 Estimated number of species, 20. 

 " The species of Ornithoptera, unrivalled in size and 



