50 ITCH-MITES. 



Illinois and Minnesota. The leather from the hides appeared 

 disfigured with pits from one to six millimeters in width, 

 w^hich in many cases penetrated nearl3^ through its entire 

 thickness. 



B. ITCH-MITES. 



{Sarcoj>tkl(t'). 



In former times, and even quite recentU^, doctors did a 

 very strange and unheard of thing ; they disagreed among 

 themselves, and this about the cause of a well-knovk'n disease 

 called the itch. They did so because the\^ could not always, 

 easily and readily find the itch-mites in the burrows made by 

 these parasites. Consequently other explanations for the 

 itch were given such, as "special fermentations," "thickened 

 bile," "irritating salts," "drying of the blood," "melanchoHc 

 juices," and other equally convincing ones. During the late 

 war, when the itch became very common, and for some very 

 good reasons too, they invented such terms as "army itch" 

 or "seven-\'ear's itch." A soldier having the latter disease 

 could of course not expect to become, well in a few days or 

 weeks, and was consequently sent home to spread the itch 

 among other people. 



Itch-mites are the cause of a disease called acariasis or 

 itch in man, of mange in horses, hogs, dogs, and cats, and 

 of scab in sheep and chickens. Wherever this disease occurs 

 it is invariabh' caused by these parasites, which burrow in 

 self-made tunnels in the skin of their hosts, live free upon 

 them or snugly hidden under scales or hairs. They either 

 feed upon the blood of their host, or gnaw and destroy the 

 younger epidermal cells. It has been claimed, but not proven, 

 that these mites inject a poison in the skin to cause a more 

 rapid flow of blood to the injured spot. Since these mites 

 live in or upon the skin all internal applications or remedies 

 are in vain, because they do not reach the source of the evil, 

 and can not kill the invaders without killing the host. 



The itch-mites, a number of \vhich are illustrated, have 

 flat bodies, with a striated skin, and a roundish or squarish 



