272 VEGETABLE FOES AND DISEASES 



in early stage, then resembling a blister, but depressed : 0, 

 blotch. D, fruit affected with black spot in an advanced 

 stage : /, black spot. E, Black Spot fungus (Macrosporium 

 tomato): f, conidia in various stages of development, x 300. 

 F, detached conidia of Macrosporium tomato, one germinat- 

 ing : r > germ tube. 



TURNIP "FLY" OR "FLEA" (Phyllotreta nemorum). 



The Turnip Fly or Flea is a small beetle (A, p. 

 278), about one and a quarter line long ; black, with a 

 broad yellow stripe down each wing-case (elytra). 

 The antennas have three joints near the head, ochre- 

 ous, and eight dark-coloured joints. Legs ochreous, 

 thighs stout, hence well adapted for jumping ; it often 

 takes leaps of twelve to eighteen inches. It has also 

 large and powerful wings (A, c) over a quarter of an 

 inch in expanse, therefore capable of long flights, un- 

 doubtedly smelling its food from a distance. It at- 

 tacks the young Turnips and other Brassicas, biting 

 and devouring their soft tissues, and lays eggs on the 

 second or rough leaves (B), choosing the under side. 

 From the eggs minute yellow grubs or larvae hatch 

 out in seven or eight days (C), and make mines (D) 

 in the leaves, feeding upon the soft tissues and corres- 

 pondingly injuring the plants. The grubs or larvae 

 are, when full grown, about two and a half lines long, 

 with three pairs of feet and a caudal " sucker foot," 

 and have dark marks upon the anterior and posterior 

 parts of their bodies. In the course of five to seven 

 days they fall to the ground and change to pupae (E), 



