OF THE FARM AHD GARDEH. 263 



pot. As the use of smoke in the small way is incon- 

 venient, and as there is a risk of injuring the plants by 

 over-heating, it is better to apply tobacco in the liquid 

 form. The cheapest kind of tobacco are the " stems," 

 really the mid-ribs of the leaves, removed by the cigar 

 makers. Either these or cheap tobacco of any other kind, 

 may be placed in any convenient vessel and covered with 

 water. The infusion thus made will be too strong to ap- 

 ply to the plants, and when used should be diluted with 

 water until it is of the color of ordinary tea. The plants 

 may be syringed with this, or it may be applied with the 

 watering-pot, as suggested for the use of water. The 

 most thorough method of using tobacco-water, and on 

 the whole the most convenient, is to have it properly di- 

 luted in a deep tub or barrel, and to dip the plants in it, 

 moving them up and down a few times before removing 

 them. If this can be done once a week the plants will 

 be kept free from most insects. 



The insects which attack flowering plants in the open 

 air only, are chiefly the Rose-bug and the Rose-slug, 

 though grasshoppers, when abundant, are sometimes 

 troublesome. The Rose-bug by no means confines itself 

 to the plant from which it takes its name; it is described 

 under the Insects Injurious to the Grape-vine on page 245. 



THE ROSE-SLUG. 

 (Selandria rosce, Harris.) 



The main points in the history of this well-known gar- 

 den pest are given by Harris in his "Insects Injurious to 

 Vegetation," etc. It undoubtedly originated in New 

 England, probably upon Rosa lucida or R. Uanda, as 

 these are the species of wild Rose upon which it prefera- 

 bly feeds. Dr. Harris first observed it in the gardens of 

 Cambridge, Mass., in 1831, and observes that six or seven 



