218 VEGETABLE FOES AND DISEASES 



THE ILLUSTRATIONS REPRESENT CLUBBING IN CABBAGES, FINGER-AND- 

 TOE IN TURNIPS. 



A, clubbed Cabbage plants : a, young plant from seed or pricked 

 off bed at stage of lifting for final transplantation ; b 9 trans- 

 planted plant with disease fully developed ; c, swollen and 

 clubbed condition of root-stem ; <4 stunted and blackened state 

 of leaves in advanced stage of disease. B, Turnips attacked by 

 club-root fungus : , seedling Turnip with finger-and-toe ; f t 

 young Turnip showing wart or knob malformation. C, 

 normal cells (cellular tissue) of Cabbage root-stem, x 200. 

 D, cellular tissue of Cabbage root-stem with club-root 

 fungus : g, cells containing plasmodium ; /&, cell crowded 

 with spores of the fungus, x 300. E, spores of club-root 

 fungus, Plasmodiophora brassicae. x 670. F, spores germin- 

 ating : /, spore with protoplasm protruding ; j, plasmodium 

 consisting of naked protoplasm emerged from spore ; k, a plas- 

 modium after union with another, x 670. 



CARROT FLY. (Psila ros*e.) 



The Carrot Fly is shining black slightly tinged 

 with a greenish colour. It has yellow legs, white 

 " balancers," and hyaline transparent wings ; the head 

 is reddish-yellow, and the antennae and palpi tipped 

 with black. The larva is cylindrical, and of a pale 

 yellow colour ; the body tapers slightly towards the 

 mouth, while the other end is rounded ; its skin is 

 smooth and shining, the tail has two little black 

 tubercles. The pupa is light brown in colour and of 

 long-oval form. 



The damage done by the larva, popularly termed 

 grub, maggot, and worm, of the Carrot Fly is known 



