MOWERS. MITES. 



67 



Fig. 59. PHALANGIUM. 



29. In this order are 

 placed mites, the mow- 

 ers (p/talan'giu?n), &c. , 

 so remarkable for the 

 length of their legs (Jig. 

 59). Their mandibles 

 are shorter than the 

 body, and their eyes are 

 borne on a common 

 peduncle. They are 



very active ; some live on the ground, and others on trees. 



30. The tribe of ACA'RIDES or mites is composed entirely of 

 very small or microscopic Arach'nidans. Their habits vary very 

 much. Some live on the ground under 



stones, or on plants ; others are aquatic ; 

 some are only found in organic substances, 

 which are more or less changed, as old 

 cheese, &c. ; and there are some that live in 

 the skin or flesh of different animals. A 

 species of mite, the Icplus autumnalis, very 

 common in autumn on wheat and other 

 plants, insinuates itself under the skin and 

 occasions an almost insupportable itching. 

 To one genus of mites, called Sarcop'tes 

 (from the Greek, sarx, in the genitive, sarkos, 

 flesh, and koptein, to cut), is due that loath- 

 some disease the itch. This a'carus is repre- 

 sented (fig. 60) magnified. Other parasitic 

 arach'nidans attach themselves to dogs, oxen, &c., and are known 

 under the name of ticks, &c. 



Fig. 60. A'CARUS. 



29. What are mowers ? 



30. What are Aca'rides ? 



What is the cause of itch ? What are ticks ? 



