246 BERTHA'S VISIT TO HER 



facts in the Dialogues on Entomology, which my 

 aunt lent me last month. 



There is another species called the oak 

 puceron, which bury themselves in the crevices 

 of the bark when it is a little separated from 

 the wood, and live at their ease on the sap. 

 They are black, and nearly as large as a com- 

 mon house-fly. Their trunk is twice the length 

 of their bodies, and it holds so fast by the wood, 

 that, when pulled away, it frequently brings a 

 small piece along with it. Ants are so fond of 

 this species of puceron, that they are the surest 

 guides where to find it ; for whenever we see a 

 number of ants upon an oak, and all creeping 

 into one cleft of the bark, we may be certain, my 

 aunt says, of finding quantities of oak pucerons 

 there. 



Mary, two or three days ago, raised the turf 

 in different places in a dry pasture field, and 

 shewed me clusters of ants gathered about some 

 large grey pucerons. My aunt says that these 

 earth pucerons draw the juices from the roots of 

 plants, as the other species do from the stem and 

 branches. It is imagined by some people, that 

 they are only the common pucerons, which in 

 winter creep into the earth to shelter themselves : 

 but this is not the case, as they are usually met 

 with in places distant from the trees or plants 

 on which they might before have fed. And she 

 says, that though many may be killed by the 



