46 STRONG DRINK AND TOBACCO SJfOKF. 



grow very fast, and in a few days become green lice, 

 whicli is merely a larger form of the same animal. 

 These lice very soon begin to breed, and so keep on 

 knits and lice, knits and Uce only, to so great an 

 extent as to destroy the plant, when they appear to 

 die with it. I have never found that the deposit of 

 the hop fly leaves the plant at all, or ever becomes a 

 fly while there ; in this respect differing from the 

 aphis of the rose, guelder-rose, bean, &c. Frequently, 

 when the weather in May has been dry and cold and 

 windy, the fly has been known to leave the plant 

 and entirely disappear, even after remaining several 

 days. The direction of the wind has nothing what- 

 ever to do with their first appearance ; liut in a warm 

 westerly wind they will take flight most readily, and 

 be thus distril3uted. 



" You will never find a plant of any kind infested 

 with the aphis, without also observing a number of 

 ants and lady-birds among them, and also a queer- 

 looking insect like a fat lizard, whicli is, in fiict, the 

 caterpillar of the lady-bird. The connexion of the 

 ants and the aphis is of the most peaceful kind that 

 can be conceived : their object is the honey-dew whicli 

 the aphis emits ; and far from hurting the animal 

 which aff"ords them this pleaso-nt food, they show it 

 the greatest possible attention and kindness, licking it 

 all over with their little tongues, and fondling it and 

 patting it and caressing it with their antennae in the 

 kindest, prettiest way imaginable. Not so the lady- 



