^^S. THE PLANT L0US2= 



Genus IX. — //phis. 'J^he Plcmt Loufe, 



X EW infects are mere common than thefe, while few 

 prefent greater Angularities to the obfervation of the na- 

 turalift. Plant lice are feen on the leaves of a great va- 

 riety of plants, and often in focisty, and in confiderable 

 numbers. At certain feafons, they are viviparous, and 

 at others they produce inanimated eggs, which remain in 

 that ftate till the action of the fun call forth tlieir vital 

 powers. The foetus, when the parent is viviparous, 

 fhews figns of life before it is fairly excluded from the 

 body. Sometimes the fame mother gives birth to near 

 twenty in a day, vrithout appearing lefs in bulk than be- 

 fore *. If one of thefe pregnant females are taken and 

 preffed between the finger and the thumb, a ft ill greater 

 nuraber of j'oiing will be forced from her body, one fol- 

 lowing another like a (Iring of beads, and growing fraal- 

 ler and fmaller, in proportion as their period of natural 

 delivery was more remote. 



Reaumur is of opinion that fecundation is performed 

 among the females of this tribe, without copulating with 

 the malef ; and the experiments of fucceedlng naturalifts 

 have confirmed an affertion that feems to be contradi6led 

 by the analogy of all animated nature. Tske a plant 

 loufe, the inftaut'it iffues from its mother; fhut it up 

 carefully from all accefs to congenerous animals ; and if 



it 



* Reaumur, Tom. III. p. 29I. 



f Memoir, pour fervir a L'liiH ties InfeiScs, Tom. III. mem. 9^. 



