

124 ; THE INSECT WORLD. 
look upon it asa female. From that day up to the 20th, inclu- 
sive, she produced ninety-five little ones, all alive and doing 
well, the greatest number of which were born under my own 
eyes !’’* 
He very soon made some other experiments on the aphis of the 
elder-tree, so as to assure himself if the generations of plant-lice, 
reared successively in solitude, preserved the same property of 
procreating without copulation. 
“On the 12th of July,” says he, “about three o’clock in 
the afternoon, I shut up a plant-louse that had just been born 
under my eyes. On the 20th of the same month, at six o’clock 
in the morning, it had already produced three little ones. But I 
waited till the 22nd towards noon, before I shut up a plant-louse 
of the second generation, because I could not manage earlier to be | 
present at the birth of one of those produced by the mother I had 
condemned to live in solitude. I always continued to observe the 
same precaution. I shut up only those plant-lice which were born 
under my very eyes. A third generation began on the Ist of 
August; it was on this day that the plant-louse I had shut up 
on the 22nd of July gave birth to this generation. On the 4th of 
August, about one o’clock in the afternoon, I put into solitary 
confinement a plant-louse of the third generation. On the 9th of 
the same month, at six in the evening, a fourth generation, due | 
to this last one, had already seen the light: it had given birth 
to four little ones. On the same day, towards midnight, all com- . 
merce with its own species was forbidden to the plant-louse of the 
fourth generation, born at that hour. On the 18th, between six 
and seven o’clock in the morning, I found this last in the company 
of four little ones, to which it had given birth.” + 
In this case, the want of food caused the death of the isolated 
individual of the fifth generation, and the experiment was brought 
to a close. 
Bonnet then tried experiments on the plantain aphis, following 
them up during five consecutive generations, which succeeded each 
other without interruption, in the space of three months. 
* Traite d’Insectologie, ou Observations sur les Pucerons ;’’ lre partie, 18mo, 
Paris, 1745, pp. 28—38. 
+ Ibid. pp. 67—69. 
