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 Natiirlichen Pflazenfamilien. 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—I, II, 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, Zoocecidies des Plantes d'Europe , the number being 
that appended to the gall therein. 
Plowright, Monograph of British Uredineae and Ustilagineae. 
Buckton, Monograph of British Aphides. 
Cameron, British Phytophagous Hymenoptera. 
