LIST OF PLATES 
Those in colour are marked with an asterisk 
PLATE FACING PAGE 
I. *THE OYSTER-GALL AND ITS INFLUENCE ON THE 
COLORATION OF OAK LEAVES - - - 6 
II. *WILLOW LEAVES WITH GALLS CAUSED BY SAW- 
FLIES - - - - - 22 
III. *GALLS ON LEAVES OF WILD ROSES - frontispiece 
IV. *THE OAK-APPLE AND ITS ALTERNATE FORM - 34 
V. *OAK SPANGLE GALLS WITH THEIR ALTERNATE 
FORMS - - - - - 36 
VI. *GALLS CAUSED BY BEETLES - - - 50 
VII. *SOME GALL-CAUSING MOTHS, WITH THEIR GALLS- 56 
VIII. *GALLS CAUSED BY THE LARVAE OF FLIES (VARIOUS 
GENERA) - - - - - 66 
IX. *GALLS CAUSED BY THE LARVAE OF FLIES (GENUS 
OLIGOTROPHUS) - - - - “70 
X. ^CONCERNING CHERRIES STROBILOBIUS - - 82 
XI. TUMOURS ON A BRANCH FROM AN APPLE TREE - 86 
From a photograph by Mr. Roger Hutchinson, M. R.C S. 
XII. *GALLS ON LEAVES OF ASH AND POPLAR - - 88 
XIII. *MITE GALLS ON SYCAMORE AND MAPLE - • 98 
XIV. BEECH TRUNK GALLED BY MITES (?) - - 104 
From a photograph by Mr. Sydney Webb. 
XV. EELWORM GALLS ON MILFOIL LEAVES - - IIO 
Reproduced from “ British Vegetable Galls,” by permission of 
Messrs. Hutchinson and Co. 
XVI. *GALLS CAUSED BY FUNGI AND MYCETOZOA - Il6 
XVII. “WITCH’S BROOM” ON SPRUCE BRANCH - - 1 18 
From a photograph by Miss Truda Hutchinson. 
XIV 
