84 THE APHIS VASTATOR ON OTHER PLANTS. 



was growing in fields, and I have not unfrequently found 

 every leaf so densely covered with this pest that scarcely 

 any portion of the leaf was visible between the insects. 



(335.) Their effect upon the nigrum and dulcamara, 

 when in a wild and natural state, is to destroy each leaf 

 separately, and in this way gradually to kill the plant. 

 Upon some large, luxuriant specimens, which were growing 

 on a dunghill, the insect was very abundant, and I found the 

 roots gangrenous and ulcerated just below the ground, 

 showing a similar character to that evinced by the potatoe. 



(336.) Besides these solani, I have found it upon many 

 greenhouse and other species, of which I need not enume- 

 rate the names, the fact being of importance only as show- 

 ing the preference evinced by this aphis for this genus of 

 plants. 



(337.) The Atropa belladonna is in like manner affect- 

 ed; and I find quantities of the vastator on these plants in 

 various situations. 



(338.) I have also observed the vastator on a species of 

 henbane, growing in the garden of Finsbury Circus ; and 

 I have just received a plant of the hyoscyamus from Staf- 

 ford, with plenty of these insects feeding on it. 



(339.) These creatures do not appear to me to like the 

 tobacco plant, for after examining many species I have 

 failed to detect a single insect, either in its winged state, or 

 as a larva or pupa. 



(340.) The stramonium is attacked by this creature, 

 and its large leaves are often totally destroyed by its ra- 

 vages. 



(341.) In all these instances, the effects noticed are pre- 

 cisely analogous to those presented by the potatoe, but in 

 these instances, the plants resist the attacks of the vastator 



