lluS CLASS INSECTA. 



THE THIRD ORDER OF INSECTS. 



The Parasita, Lat., Anoplura, Leach, 



Thus named from their habits, (see lower down,) have b\it six 

 feet, and are apterous, like the thysanoura ; but their abdomen 

 has no articulated and mobile appendages. For organs of sight 

 they have but four or two small simple eyes. Their mouth 

 is in a great measure interior, and presents externally either 

 a muzzle or mammella, enclosing a retractile sucker, or two 

 membranous and approximating lips, with two mandibles 

 crotchet-formed. They form, in Linnaeus, only the genus of 



The Lice, (Pediculus,) Lin. 



Their body is flatted, almost transparent, divided into 

 twelve or eleven distinct segments, of which three are for the 

 trunk, each having a pair of feet. The first of these seg- 

 ments often forms a sort of corslet. The stigmata are very 

 distinct. The antennae are short, of the same thickness, com- 

 posed of five articulations, and often inserted in an emargi- 

 nation. Each side of the head presents one or two simple 

 eyes. The feet are short, and terminated by a very strong 

 claw, or by two crochets directed one towards the other. 

 These animals thus crook themselves easily, either to the 

 hairs of quadrupeds, or the feathers of birds, the blood of 

 which they suck, and on the body of which they pass their 

 lives and multiply. They attach their eggs to these cuta- 

 neous appendages. Their generations are numerous and 

 succeed each other with great rapidity. Some particular 

 causes, which are unknown to us, favour them in an extra- 

 ordinary manner, and this is exemplified in regard to man, 

 in the pediculary malady, or phtiriasis, and even in our 



