132 



ACAEINA OR MITES. 



-sd 



Fin. 68, — Dr-^roDECTic Scabies. Section of 

 skin, magnified forty dianieter.s. (L.iulani6.) 



c, Epidermis ; /, hair follicle ; P, hairs : h h', 

 bulb.s of hairs ; a to a**", dilations due to l>emo- 

 dox accumulations, d ; sb, sebacious glands ; 

 sh\ gland with Di'inodex ; sd, sudoriparous 

 glands. (From Neumann.) 



this form may possibly 

 be transmitted to man 

 and other animals. The 

 female Sarcopt lays her 

 eggs in tunnels in the skin, 

 not under the scab as in 

 Psoroptes. Then small 



I papules appear on the 

 skin, which on being 



^ rubbed pass out a clear 

 exudate, hardening and 

 forming a crust or scab 

 of a dirty - grey colour. 

 The skin becomes hard 



sb and deeply folded, and 

 blood may be seen oozing 



si out in the cracks. 



The third form, Sym- 

 biotes commtinis v. ovis, is 

 not of common occurrence. 

 The Symbiotes live in col- 

 onies, but do not excavate 

 any sub-epidermic galleries. 

 They are oval, not rounded, 

 and the legs are longer and 

 more easily seen. The legs 

 are cliiefly attacked by this 

 form of mite, similar to the 

 attack in the horse, pro- 

 ducing red patches on the 

 skin and very thin scabs. 

 It is of little importance in 

 Britain. 



Varieties of Sarcoptes, 

 Psoroptes, and Symbiotes 

 are also found on the 

 horse, pie:, ox, aroat. dog. 



