Galls caused by the larvae of Rhodites eglanteriae Htg. 



on 



the leaves of Rosa canina Linn. 

 PLATE 112. 



Synonymy of Insect. 



Hololexis eglanteria: Foer. 



Rhodites eglanterice Schenck, Mayr, Taschen., Thorns., 

 Fitch, Cameron. 

 Habitat of the Dog-rose. — This is the commonest rose 



in Britain, and grows rapidly and luxuriantly in hedges, 



thickets, and various dry places in all parts of the country. 

 The Gall is formed by an enormous accumulation of sap 



drawn from the leaf, which passes through the slender 



pedicle with very great rapidity. 

 Position.— On the upper as well as the lower surfaces of the 



leaf, on the petioles, and occasionally on the stem. 

 Manner of Growth. — Globular ; singly ; glabrous ; never 



united, although the swellings may be very close together. 

 Colour — Pale green, suffused with pink or red. 

 Average Dimensions of a Mature Specimen. 



Girth, IS mm. 

 May be sought during the months of July, August, Sep- 

 tember, and October. 

 The Growth is complete by the end of September. 

 The Typical Condition of the gall is unilocular and 



unilarval. 

 The Larva pupates in the gall. The imago emerges during 



the following spring. 

 InquilINE. — Periclistus canines Cam. 

 Parasites. — Hemiteles imbeciliis Gr., Toryimis difficilis Nees., 



T. congener Foer., Oligostemis stigma Fab., Eulophus 



inunctus Nees. 



The gall is also figured by Peter Cameron, " British 

 Phytophagous Mymcnoptcra" (Ray Society), vol. iv., plate ii. 



255 



