Forest entomology

Preface

In submitting a book on a branch of Natural Science which has required any degree of research during its preparation, or which otherwise is intended as a guide for research, perhaps no one realises its shortcomings more than the writer. At least this is certainly the feeling of the author on the present occasion.

The book was begun in a very humble way. Having always had a strong inclination for Natural Science, and further for studying subjects associated with the scientific aspect of forest trees, I began as far back as 1887, while residing in Cheshire, to write papers on Forest Insects for the Warrington Field Club. To that district, with its Natural History clubs or societies, and the many excellent men I met in connection with them, I owe a very deep debt of gratitude. I cannot in the present circumstances enumerate all to whom I am indebted for assistance in the present book, but my first teacher in Entomology was the late Mr Berry Kendrick of Warrington, who gave me most ungrudgingly all the help any one could possibly give to a beginner. Of the Warrington Field Club itself it is impossible to speak too highly as a Natural History society. Composed of some fifty members*

Vlll

PREFACE.

original papers were given every fortnight during the winter months, often accruing from investigation during the summer months, and the members freely criticised the paper of the evening. This, though perhaps not always appreciated at the time, was in itself a most excellent school.

In a similar way I am indebted to the Manchester Microscopical Society for a great deal of ready help from its members. This Society, unlike the former, published the papers of its members, and I have therefore to sincerely thank it for publishing my papers on “ Forest Insects,” and, further, for kindly giving me the blocks prepared from my own negatives, some of which I have used for the present book.

I have also to thank the Chester Society of Natural Science for many extended courtesies given from time to time. The material for this book has been collected in Cheshire and Northumberland, but more especially the former county.

I am also indebted to the Country Gentlemen’s Association, the Highland and Agricultural Society of Scotland, and the Royal English Arboricultural Society for publishing papers on Forest Entomology.

Turning from societies to individuals, it is almost impossible to acknowledge without being invidious those who have assisted me in the subject - matter of the volume. Two names may be mentioned. Mr R. Newstead, author of ‘A Monograph of British Coccidte,’ gave me from time to time much assistance on Scale Insects. Mr A. Flatters, Manchester, has given me great help in microscopical manipulation, and has, in addition to the figures acknowledged with his name, photographed several specimens from my own microscopic slides, as, for example, the tiny Cecidomyia Hies.

As regards the first works from which 1 derived considerable assistance, I may specially mention ‘A List of Insects on

PREFACE.

IX

Forest Trees/ by Mr S. L. Mosley, Huddersfield, and the splendid ‘ Manual of Injurious Insects ’ by the late Miss Ormerod. Of the latter I cannot speak too highly, more especially as Miss Ormerod gave me very great encouragement by correspondence.

As the period during which I have studied the subject has extended over twenty years, it is obvious that much original work has been done by many workers during that time. I have tried, so far as means or leisure would afford, to keep in touch with all original work. In order, therefore, that the student may get the full advantage of that, I have, whenever I found the work of others more suitable than my own, quoted from those writers. In most cases this has been done by direct permission of the author, but in all cases when giving an extract I have endeavoured to duly acknowledge the same. In this advanced age of ours, knowledge, more especially Entomological knowledge, is no longer the property of any one individual. Hence all quotations are freely given as epitomised knowledge suitable for the student. They are given to obviate at first the necessity of consulting other works, and yet at the same time be a guide as to what other works he may consult for fuller information. It will be apparent that the majority of quotations are of a systematic nature. Hence the great difficulty in preparing the book has been to amalgamate the systematic with the economic, and so maintain a due proportion. On the one hand, if too many details of a systematic nature were given, the work would not only have been very much overladen, but the practical man would be impatient in reading it : on the other hand, if too few systematic details were given, it would not act as a guide to fuller inquiries, or form, as designed, a suitable text-book for students at agricultural and other colleges. The main

X

PREFACE.

feature which is attempted is recognition of tlic insect from the damage, together 'with systematic characters ancl life-history details.

In studying the subject from the economic point of view, I have become convinced, from a prolonged study of the subject, that the economic student must of necessity study the systematic side and associate himself with systematic men. Hence, for example, I have added often, in extenso, extracts from valuable works like Fowler’s £ British Coleoptera,’ &c. At the same time, the matter is so arranged that the beginner, or the practical man, may at first, if he chooses, skip them, and study the nature of the injuries, the life-history of the insect, and in some cases the remedies which may be adopted. If, however, the subject is to be thoroughly studied, the systematic points must be ultimately mastered.

With a view of making the work more reliable, I have submitted each chapter in proof to men who have specially studied particular sections or families of insects, and in all cases I am glad to count these specialists as personal friends. As the work embraces nearly all families of insects, this was considered all the more advisable, and though the changes made in the proof form by these specialists were comparatively few, yet in every case they were most important from the systematic point of view.

The following are the names of those who looked over the respective chapters in proof form — viz., Mr E. T. Connold, “ Gall-Mites ” and “ Oak Galls ” ; Mr E. S. Baguall, “ Coleoptera ” ; Mr A. C. Forbes, “ Scolytidse ” ; Eev. F. D. Morice, “ Saw - flies ” ; Mr E. Newstead, “ Scale - Insects ” ; Mr J. Collins, “ Lepidoptera ” ; Mr F. V. Theobald, “ Aphididse ” and “ Hiptera.”

I have also to thank Mr J. F. Annand, Lecturer on forestry.

PREFACE.

XI

Armstrong College, Newcastle, for kindly looking over the MS. previous to sending it to the publishers, and also for discussing many of the practical points with me.

I am specially indebted to Commander J. J. Walker, E.N., Oxford, for kindly correcting the final proofs.

With reference to the illustrations, for the loan of blocks or electros I am indebted to Messrs Sampson, Low, Marston, & Co., Ltd., for figs. 14, 16, 20, and 21 ; to Professor Miall for fig. 18 ; to Messrs L. Reeve & Co. for figs. 39, 41, and 42 ; to the Ray Society for figs. 202 and 210, and also for granting permission to photograph figs. 213, 214, 280, 282, 284, 287, and 311 ; to Messrs Headley Brothers for figs. 175, 22 1 , and 270 ; to the Proprietors of ‘ The Entomologist’s Monthly Magazine’ for figs. 157, 158, and 159. Mr W. R. Pisher has given me much encouragement from time to time, and I have to thank him for receiving from Messrs Bradbury, Agnew, & Co., Ltd., the large number of blocks — viz., figs. 47, 48, 49, 50, 60, 61, 78, 79, 92, 121, 126, 127, 163, 164, 238, 239, 240, and 241. I also owe thanks to Messrs Blackwood for figs. 45, 46, 72, 73, 79, 101, 102, 104, and 245, from ‘ The Forester,’ by Dr J. Nisbet. With the exception of the figures taken from the valuable German works, and acknowledged under each figure respectively, all the others are original.

Finally, I beg to say that I submit the knowledge contained in the book with a feeling that I have just about the necessary amount of knowledge to make a beginning rather than a finish ; and I trust that the student will take up the subject with the object of making a study of it on his own account, and verify each point by observation and rearing. In other words, the student must consider the work as an introduction only. Further, there is the most important point left

Xll

PREFACE.

to the last — viz., the study of German literature. The Germans are our great teachers in this branch of knowledge, and I have added many points and illustrations from German sources with the distinct object of showing their superiority, and inducing students to study their most valuable works.

Park Cottage, Alnwick, May 1908.

Contents

PREFACE vn

INTRODUCTION . . • • • 1

I. ERIOPHYIDiE (PHYTOPTIDA:) OR GALL-MITES . . • 19