26 COEN AND GRASS. 



Aphides have their winter habitat, but from the fact of these Aphides 

 being found in other countries sheltering at the roots of Grass or corn 

 during the winter, it is very probable that they do the same here, 

 whether in egg or active state, although (so far as I am aware) we have 

 not yet had any definite observation of this happening. But this 

 would, I think, agree with your own remark that ' they appear most 

 troublesome on land that has been laid away for two or three years 

 Grass, and so far they have not touched the one-year Grass and 

 Clover.' 



" At this time of year the infestation is to be found on the blade or 

 stem of the corn, or, in your case, of the Grass, where (as your speci- 

 mens show) they can do enormous mischief. This is not only by 

 drawing away the juices by means of their suckers, but also by the 

 great damage caused to the tissues from the Green Fly (from their 

 first production) driving their suckers into the soft parts. 



** I never yet saw such a severe Grass attack, and I am sorry to say 

 that they may be expected to multiply rapidly. At this time of year 

 and till autumn, they multiply by being produced alive, all ready fur- 

 nished, like the fully developed specimens, with six legs adapted to 

 active movement, and a sucker for piercing into their food-plants ; and 

 such of the females as pass to the winged condition carry the infestation 

 far and wide. Presently (in ordinary course) it may be feared that 

 where corn is in the neighbourhood the infestation will appear on the 

 leaves, and then do infinite mischief by extending to the ears. 



" This is the stage of attack in which (later in the year) I usually 

 receive specimens. Then these ' Plant Lice ' lodge in the ears, and 

 by piercing into the main stem and the side stems of the ear, they 

 prevent the grains swelling properly, and yield a shrivelled, more or 

 less injured return. In this condition (that is on the ears) the 

 Aphides are very often in great part brown ; but, as above mentioned, 

 there is no reason to doubt that they are of the same species as those 

 now under consideration." 



Prevention and Remedy. — In the above, or any similar case where 

 there might be a definite centre of attack in a large Grass field from 

 which the infestation was spreading, the best treatment for the safety 

 of the neighbourhood would apparently be to mow the infested Grass 

 as soon as possible, and then so to treat the short hay that it might 

 remain also for as short a time as possible, in a state for the Aphides 

 to continue to live on it. Thus all the wingless Plant Lice on the cut 

 Grass would be killed, and excepting from such of the others as might 

 fly away, infestation from this source quite stopped. 



A dressing of any kind preferred, which would both be bad for any 

 Aphides remaining on the ground, and also push on a good growth of 



