78 



Parasitic Arthropods 



Notoedres cati (usually known as Sarcoptes minor) is a species 

 of itch mites which produce an often fatal disease of cats. The body 

 is rounded and it is considerably smaller than Sarcoptes scabiei, 

 the female (fig. 6i) measuring 215-230(1, long and 165- lysfji. wide; 

 the males i45-iso[a by i2o-i25(ji. The most important character 



61. Notcedres cati, male and female. After Railliet. 



separating Notoedres from Sarcoptes is the position of the anus, 

 which is dorsal instead of terminal. The mite readily transfers 

 to man but does not persist, the infestation usually disappearing 

 spontaneously in about two weeks. Infested cats are 

 very difficult to cure, unless treatment is begun at 

 the very inception of the outbreak, and under ordi- 

 nary circumstances it is better to kill them promptly, 

 to avoid spread of the disease to children and others 

 who may be exposed. 



Demodecidae 



The Demodecidae are small, elongate, vermiform 

 mites which live in the hair follicles of mammals. 

 The family characteristics will be brought out in the 

 discussion of the species infesting man, Demodex 

 folliculorum. 



Demodex folliculorum (fig. 62) is to be found very 

 commonly in the hair follicles and sebaceous glands 

 of man. It is vermiform in appearance, and with the 

 elongate abdomen transversely striated so as to give 

 -62. Demodex foiii- it the appearance of Segmentation. The female is 380- 

 Att°er"BiaS?d. 4oo(x loug by 4S[Ji.; the male 3oo(Aby 40[ji. The three- 



