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FAMILY PLUTELLID^. 



This family is mentioned becanse it contains one 

 of our most destructive vegetable pests — the cab- 

 bage moth {Plittella crucifcrarum), a small insect 

 measuring about 1^ inches across its narrow out- 

 stretched wings. It is light fawn in colour, with 

 darker triangular markings near the inner edge of 

 the front wings. AA^hen these are closed the moth 

 has a roof -like appearance, and the triangles of 

 each wing, meeting, form a rectangle; from this 

 fact it is frequently referred to as the ''diamond- 

 backed cabbage moth." We have noticed it wher- 

 ever plants of the Cruciferac family (cabbage, 

 cauliflower, turnip, stock) were grown. Upon 

 the leaves of these plants the tiny eggs are de- 

 posited. The slender, delicate-green caterpillar, 

 less than three-quarters of an inch in length, eats 

 h.oles in the leaves and then pupates under a loose 

 silken web which it attaches to their under surface. 



Our experience in following the life history of 

 this moth proved that it occupied about 14 days 

 from the egg to the perfect insect. 



In the vegetable garden where cabbages and 

 turnips grew side by side, the former always 

 seemed to have the preference as a food plant for 

 the larv«. Stocks growing but a few yards distant 

 were riddled to such an extent that there was not 

 a chance of their recovery. Two or three years 

 iu succession we have noticed what seemed to us 

 a decided preference for stocks over the vegetables 

 of the same family. 



