122 APTERA. 



or three times, are ready to produce in their 

 turn. Experience has shown that in six days 

 a louse will produce 50 eggs. The young leave 

 the shell about the same period of time, and 

 in about 18 days more are in a state for repro- 

 duction. From these observations, and the cal- 

 culations arising from them, it appears that two 

 females may have 18,000 little ones in the space 

 of two months. 



Oviedo makes a singular remark, though un- 

 supported by proof. He says that the lice 

 quitted the heads of the Spanish sailors in a 

 certain latitude, while on their voyage to India, 

 and returned to them again, in the same lati- 

 tude, in their way back. 



Hottentots and monkeys seem to delight in 

 the filthy custom of eating these insects, and 

 there is reason to believe that the same nau- 

 seous inclination prevails among the lower class 

 of the Russians. 



Most of the quadrupeds and birds seem to 

 have their peculiar species of this disgusting 

 genus, and even fish and insects are not totally 

 exempt from them. 



