Galls caused by the larvae of Rhodites rabiginosse 



on 



the leaves of Rosa rubiginosa Linn. 



PLATE 116. 



Habitat of the Sweet-briar. — This plant is not often met 

 with in its wild state. It is rare in all parts of Britain, 

 except the southern and eastern counties of England, 

 where, however, it grows but sparsely in hedges and 

 thickets. Under cultivation it is found in gardens and 

 parks rather plentifully. 



The Gall is formed by ova being deposited in a leaf-bud, 

 each ovum becoming surrounded with layers of sap. 



Position.— On the leaf 



Manner of Growth.— Solitary ; sessile ; globular ; covered 

 with moss-like hairs. 



Colour. — Greenish, pink, or crimson. 



Average Dimensions of a Mature Specimen. 

 Diameter, 25 mm. 



May be sought during any month in the year. 



The Growth is complete by the end of August. 



The Typical Condition of the gall is plurilocular. Usual 

 number of cells, 20. 



The Larv^ pupate in the gall. The imagines emerge 

 during the spring. 



These galls are very uncommon, and in some districts quite 

 unknown. The author has seen them only twice during the 

 course of several years of gall-hunting. They closely resemble 

 the bedeguar of Rosa canina, but are smaller and more fragile. 

 The fibres are more slender and more branched, but show no 

 difference in arrangement and structure. The larval chambers 

 are quite as hard and as numerous as those of R. rosce. 



The illustration is of specimens gathered at Hastings by the 

 author 



264 



