INSECTS ARACHNIDA DIAGBAM 6 



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throws the corpse away, or sometimes surrounds it with silken 

 threads and leaves it where it is. It repairs the meshes which 

 have been broken, and returns to wait for another victim. All 

 spiders do not lead this sedentary existence ; some species do 

 not make a web, and simply stretch threads here and there. 

 They are found running in the fields, and some of them leap 

 with great agility. They are called running and hunting 

 spiders. 



Spiders are sometimes found which carry a large silken ball 

 attached to their abdomen which they never abandon. This 

 ball is filled with eggs which the female carries everywhere with 

 her. Other species also put their eggs into a a silken bag, but 

 they hang it in some part of their web where it will be 

 secure. 



It was formerly pretended that there was a spider in Italy 

 called tarantula, the bite of which causes a desire to dance ; 

 but this is a fable, like so many other tales which are told of 

 animals. 



Mites and the itch-insect. The mites which .live in 

 cheese iiave also eight legs, and consequently 

 belong to the class Arachnida. Their history 

 would not be very interesting if their form 

 did not resemble that of another animal which 

 is a parasite on man, and which produces 

 the disease called the itch. It is still smaller 

 than the cheese- mite, and makes galleries 

 of about a quarter of an inch in length, 

 under the epidermis." As it works chiefly at 

 Itch-mite night, it is then that it causes the most 



highly magnified, violent itching. The itch is caught by contact 

 with an infected person, when the itch-mite passes from one 

 person to another. It is always desirable to get rid of these 

 parasites as soon as possible ; but as they are very small and 

 hidden under the skin, medical assistance is necessary. The 

 dog, cat, horse, and dromedary have parasites which cause itch 



