128 BRITISH GALLS 



of British plant-galls appears to be a botanical one, and 

 such is here adopted. The families are arranged as in 

 Engler's Die NatUrUchen PflazetifamiUen. For the nomen- 

 clature of species I have followed the tenth edition of the 

 well-known London Catalogue of British, Plants. 



The separate tabulation of galls caused on various parts 

 of a plant by the same causer has not been attempted, 

 because it involves too much repetition of names. The 

 galls under each plant are arranged according to their 

 causers, and in the sequence set forth above. 



To facilitate easy reference, the section to which the 

 causer belongs is indicated in the left-hand margin of the page. 



The name in italics which, in a few cases, immediately 

 follows the description of the gall is that given to it by 

 writers before its character was properly understood. The 

 number that follows the reference to the imago indicates 

 the year of its emergence — 1, 11, and so on. 



The term "aphis" concerns the apterous viviparous 

 female. 



" M. G." denotes that metamorphosis takes place within 

 the gall ; " M. E." that the larva pupates in the earth. 

 The illustrations in this volume are cited within brackets. 

 The synonymic names (in italic type) precede the citation 

 of authorities, and both follow the name of the causer, 

 which is in heavy type, and is followed by a number in 

 the right-hand margin of the page. The references to 

 authorities should be read in connexion with the more 

 detailed description in the alphabetical bibliography which 

 follows. It may be remarked that in all cases, unless 

 expressly stated otherwise, the references to the following 

 authors concern their works here mentioned : 



Houard, Zoocicidies des Plantes d' Europe, the number being 

 that appended to the gall therein. 

 Flowright, Monograph of British Uredineae and Ustilagineae. 

 Buckton, Monograph of British Aphides, 

 Cameron, British Phytophagous Hymenoptera, 



