62 THOSE OTHER ANIMALS. 



the termite, produce eighty thousand per day, the argument 

 that the whole of the rose trees in a garden have been 

 covered by the offspring of comparatively few females who 

 found their way there might be accepted readily enough ; 

 but the rate of increase is incredible when we know that 

 each female can produce but twenty-five young in twenty- 

 four hours. It would need, then, not a few, but an infinite 

 host of winged females, to account for the phenomenon. 

 That many may pass the winter as eggs in the bark of trees 

 and other places may be granted, but no one has yet ob- 

 served the vast hordes streaming out from their places of 

 concealment ready to start off in search of peas or beans, 

 roses or hops. Moreover, in seasons favourable to vegeta- 

 tion, when neither frost nor east winds nor prolonged wet 

 nor drought weaken the plants, and they grow robust and 

 strong, what becomes of the armies of green fly that would, 

 had the vegetation been sickly, have pounced down upon 

 it ? Nothing could be less scientific than these arguments, 

 but as somehow there is, common sense in them, they 

 commend themselves to the minds of the foolish multitude, 

 who, in spite of the teaching of their instructors, still 

 believe the evidence of their own eyes that the aphis is the 

 product of a certain unhealthy state of the juice of plants. 



But although the increase at the rate of twenty-five per 

 day by no means accounts for the almost simultaneous 

 appearance of countless millions, it is a ratio that unless 

 checked would by the end of the season absolutely cover 

 the face of the earth, for the young ones so speedily 

 become mothers that it is calculated the descendants of 

 one aphis will during the season number 5,904,900,000. 

 One objection on the part of scientific men to the 



