Xestophanes brevitarisis. 



The graceful plant which is so freely attacked by this insect 

 is a general favourite with all persons interested in botany. It, 

 however, possesses additional interest to the gallist, because of 

 the swellings caused upon its delicate and slender stems by 

 X. brevitarisis. The enormous size of some of the galls as 

 compared with the girth of the slender stem is remarkable. 

 One example may be mentioned. In a wood near Hastings 

 the author found, among other stems, one which measured 

 3 mm. only in girth. The swelling upon it was 22 mm. in 

 girth; it contained 41 cells, and occupied a space 18 mm. 

 in length. 



The galls occur mostly as conglomerated masses of cells, 

 but examples of a single cell are not uncommon. Two such 

 will be seen in the lower right-hand corner of the illustration 

 near the flower. Galls of one cell only are usually spherical 

 in shape, but when numbers are massed together they assume 

 a reniform shape, and the uneven outline then produced distin- 

 guishes them from the smooth growths caused by X. potcntilix 

 on R. reptans. 



X. brevitarisis is an interesting species to study ; but as the 

 galls will not develop so well after being severed from the root, 

 even though the stems are placed in water, they should be 

 obtained when growth is mature, or the entire plant removed 

 to a convenient place for observation. 



The illustration is of specimens gathered at Hastings by the 

 author. 



