BEAR ANIMALCULES 



361 



air-tubes, with four pairs of long legs, into which coecal 

 prolongations of the stomach pass, as seen in Fig. 315. 



Fig. 317. Mllnesium tardigradum, pig. 318. Carolina scorpion (Buthw 



x 120 times. I, mouth-parts ; b, alimen- Carolinianus). Natural size, 



tary canal ; ov, ovary. After Doyerc. 



The lowest mites comprise remarkable worm-like Acarina, 

 called Linguatulina. The young are mite-like, the body 

 spherical, with boring jaws, and two 

 pairs of short-clawed feet. Pentas- 

 toma (Fig. 316) occurs in the lungs 

 and liver of man, and in horses and 

 sheep. 



The Tardigrada or bear animal- 

 cules (Fig. 317) are a step higher 

 in the scale of mite life. In these 

 singular beings the sexual glands 

 exist in the same individual. 



Macrobiotus Americanus Packard 



is common in sphagnum swamps. Fig.ZW. Ohelifercancroides. 



Like the Rotatoria, these low mites : 



are capable of revivifying after being apparently dead and 



dried up. 



