160 THE POTATO. 



are the chief culprits. An allied species named H. nemor- 

 alis also attacks potato shoots. Slugs, which are easily 

 distinguished from snails by the absence of a shell, are 

 still more destructive to potato crops. They not only 

 attack the shoots, but the young tubers also. The chief 

 culprits are the Black Slug (Ariori ater), more or less black 

 in colour; Garden Slug (A. hortensis), small, slender, and 

 striped with grey; Yellow Slug (Limax rlavus), yellowish; 

 Field or Milky Slug (L. agrestis), greyish, arid covered 

 with a milky slime; and the Large Slug (L. maximus), 

 spotted and streaked with black, and measuring six inches 

 in length when stretched out. 



REMEDIES. Where both slugs and snails are plentiful, 

 and likely to do harm to the crops, apply a dressing of 

 equal parts of soot and lime on successive evenings and 

 mornings for three or four times, then the pests will be 

 destroyed. One application is of no service as the slugs 

 can cast oft' the lime and soot with the slime. But if 

 repeated as advised, it eventually penetrates the skin, and 

 kills the pests. Guano, nitrate of soda, and sulphate of 

 ammonia are also objectionable to slugs, so that where 

 these artificials are used slugs and snails will not be very 

 plentiful. 



[The illustrations on pp. 146, 154, 156, and 159 are repro- 

 duced, by the courtesy and permission of Messrs. Oliver 

 and Boyd, Edinburgh, from " Curtis's Farm Insects."] 



