PLATE 21 



Stems of Salix cinerea Linn. 



(Five-sixths nat. size.) 

 Galled by 



Agromyza schineri Gir. 



The stems on the opposite page illustrate the appearance of 

 these galls in the spring and summer of the year following their 

 formation. During the first summer's growth they were the 

 same size and appearance of those in plate 23, the increase in 

 the growth of the wood causing them to present a less elevated 

 condition. The holes through which the imagines emerged may 

 be distinctly seen in the centre specimen. 



The illustration is of specimens gathered at Hastings by 

 the Author. 



