ACARINA. 



636 



. Fig. 290. — Parasites. Acarina. 



1, Louse, Human ; magnified 50 diameters. 2, Acarus domesticus, Chccso- 

 ilite : under surface. 3, Acarus Scabiei, Itch-Insect ; magnified 350 dia- 

 meters. 4, Entozoon folliculorum, Grub from the human skin in various 

 stages of existence, from the egg upwards : magnified 350 diameters. (The 

 email circles near represent the objects about the natural size.) 



