Galls caused by the larvse, nymphs, and imagines of 

 Eriophyes tetanothrix IsBvis Nal. 



on 



the leaves of Salix Gaprea Linn. 



PLATE 66. 

 Synonymy of Mite. 



Cecidophyes tetanothrix Nal. 

 Phytoptus tetanothrix Nal. 



Habitat of the Sallow- or Goat-willow.— Very com- 

 mon throughout Britain by the sides of streams, marshy 

 places, damp open woods, and in thickets and hedges. 



Position of the Gall.— On the upper surface of the leaf. 



Manner of Growth. — Gregarious ; pubescent ; separate and 

 also coalescent. 



Colour. — Green, red, reddish brown. 



Average Dimensions of a Mature Specimen. 

 Height, 3 mm. ; girth, 9 mm. 



May be sought during the months of June to October. 



The Growth is complete by the end of August. 



The mites enter and leave the gall through an aperture which 

 is situated on the underside of the leaf The aperture may be 

 circular, oval, elliptical, or irregular in outline. When this 

 portion is viewed under magnification, numerous purple-coloured 

 spots can be seen studding the margin. The gall-structure is 

 pilose on the upper surface of the leaf and glabrous beneath. 

 A longitudinal section shows the walls to be very thick. The 

 interior is filled with long, thin hairs, many of which project 

 a short distance beyond the aperture. These galls occur in 

 considerable numbers, some leaves having as many as twenty-five 

 upon them. 



The gall is also figured by Murray, " Economic Entomology," 

 P- 337. 



The illustration is of specimens gathered at Hastings by the 

 author. 



164 



