4 • PREFACE . 



The contents of this volume have been arranged accord- 

 ing to their subjects, the first ten papers (omitting 3 c) 

 being almost exclusively concerned with Mimicry, Warning 

 Colours, and the Struggle for Existence in Insects, Nos. 10 to 

 13 with seasonal dimorphism, and the colour of pupae, &c., 

 as influenced by the surroundings of the larvae, No. 14 

 with Hybridisation, No. 14A with the 'Organic Selection' 

 of Baldwin, Lloyd-Morgan and Osborn, Nos. 15 to 19 with 

 systematic work upon parts of the existing Hope Collection 

 or new material which has recently been added. It should 

 be noted that Mr. Champion's paper on the Tingitidae, 

 No. 15, is founded on the study of material from many 

 collections : it is included here because a large proportion 

 of the types of the new species described are in the Hope 

 Museum. Nos. 3 c and 20 deal with the manipulation and 

 labelling of insects for collections, while Nos. 21 to 23 are 

 the Reports of the Hope Professor for the years during 

 which the materials for this volume have been accumulating. 

 I venture to hope that the contents of the volume indicate 

 some activity and energy in the Department. Great 

 encouragement has been received from the manner in which 

 naturalists in many countries have looked to the Hope 

 Museum as a centre for the study of insect bionomics, and 

 have sent material bearing on these difficult and deeply 

 interesting problems to Oxford. When the specimens now 

 rapidly accumulating have been arranged, the student will 

 have unique opportunities for the study of Mimicry, Warning 

 Colours, Protective Resemblance, and allied questions. Nor 

 will the arrangement be long delayed, for the chief part of 

 the printing, labelling, cataloguing, and preliminary group- 

 ing has already been done. 



One chief duty of our ancient University is to contribute 

 its share, and may it be a very large one, towards winning 



