Galls caused by the larvae of Ceuthorhynchus 

 sulcicoUis Gyll. 



the root of Brassica napus Linn. 



PLATE s. 



Synonymy of Insect. 



Ceuthorhynclius phnrostigma Marsh. 

 sulcicollis Payk. 



Habitat of the Common Turnit. — It may be obtained 

 from the fields of almost every farm or any greengrocer's 

 shop throughout the country. 



The Gall is formed by the irritation to the tissues caused 



by the feeding of the larva. 

 Position. — On the subterranean portion of the root, but seldom 



on the tap-root. 



Manner of Growth.— Generally gregarious ; glabrous. 



Colour. — Same as the root itself. 



Average Dimensions of a Mature Specimen. 

 Height, 13 mm. ; girth, 50 mm. 



May be sought during the months of September, October 



and November. 

 The Growth is complete by the end of October. 

 The Typical Condition of the gall is unilocular and unilarval. 



The Larva pupates in the ground. The imago emerges 

 during the spring. 



The gall is also figured by Miss Ormerod, " Injurious Insects," 

 p. 35 ; " The Roj-al Natural History," section xi., p. 151. 

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