MEMORANDA FOR THE MONTH 277 



peck at the wounded stag, until the poor Rosarian 

 is nearly driven out of his wits, as Mons. Vibert was 

 driven from his nursery near Paris to St. Denis, by 

 the ver blanc (grub of the cockchafer), which de- 

 stroyed all before it. Reaumur made a calculation 

 that, in five generations, an aphis might be the pro- 

 genitor of 5,904,900,000 descendants ; and a writer in 

 the Entomological Magazine (No. iii. p. 217) com- 

 municates the result of much careful observation as 

 follows : — ' Insects in general come from an egg ; 

 then turn to a caterpillar, which does nothing but 

 eat ; then to a chrysalis, which does nothing but 

 sleep ; then to a perfect butterfly, which does nothing 

 but increase its kind. But the aphis proceeds alto- 

 gether on another system. The young ones are born 

 exactly like the old ones, but less. They stick their 

 beak through the rind, and begin drawing up sap 

 when only a day old, and go on quietly sucking 

 away for seven or eight days ; and then, without 

 love, courtship, or matrimony, each individual begins 

 bringing forth young ones, and continues to do so 

 for months, at the rate of from twelve to eighteen 

 daily. 



What is the cure? There is none. You may brush, 

 you may powder, you may syringe, you may dip, you 

 may mix your tobacco-water — your decoction of 

 quasia ; but where the aphis has once taken pos- 



