CHAPTER in. 

 THE DISEASES OF EOOT CEOPS. 



(1) The Parasites of Beetroot {Beta vulgaris). 



The Beet Fly {Anthomyia hetce, Pig. 12). The 

 larvae of this insect feed upon and burrow into the tissues 

 of the leaves of beet plants, causing great destruction to 

 the crops. They are about one-third of an inch long, and 

 are devoid of legs. The eggs (Pig. 12 B) are small, oval, 

 white bodies with hexagonal-like markings. They are 



Pig. 12. — Beet Fly (Anthomyia beta). 



A. Beet Fly (nati size). 



B. Eggs, X 1. 



laid on the under surface of the leaves, and when hatched 

 (i.e., in iive days) the grubs attack the parenchyma or soft 

 parts of the leaves, and thereby interfere with the life 

 and nourishment of the plant. 



Under favourable circumstances, during the summer, 

 the perfect insect (Pig. 12 A) is developed from the pupal 

 stage in about fourteen days ; but if the transformation 

 from the larval to the pupal stage occurs late in the 

 season, the pupa hibernates in the ground until the 



33 D 



