THE SPIDER AND ITS ALLIES 95 



man. Liolmnum dorsatum is a common grayish species 

 with a darker dorsal band, which emits a clear fluid when 

 handled (Fig. 92). 



The Areneina, or spiders, already considered. 



The Acarina, 1 or mites and ticks, in which, as in spiders, 

 the abdomen is unsegmented, but is fused with the cephalo- 

 thorax. Mites have typically a round body. They exhibit 

 great diversity of form and habits. All are 

 terrestrial, excepting one group of aquatic 

 mites, and are often of a bright red color 

 (A tax). The free-living species prey on 

 smaller animals, as well as dead organic 

 substances. Others are parasitic in animals 



, . . f p J.T 9 i FIG. 94. Pal- 



or plants, living in fur or leathers/ and even Ien6) a sea _ 

 penetrating into the skin, as the small red spider. : 1.5. 



,, , . ,, r. ,, Photo, living 



"jigger or " c nigger ' or our bouthern byW.H.c. P. 

 States does. 



Finally, there lives in the sea an aberrant family of 

 spiders which crawl on the sea-bottom or over hydroids, 

 and thus have forsaken a terrestrial life for a completely 

 aquatic one (Fig. 94). 



APPENDIX TO CHAPTER VI 



KEY TO THE SEVEN SUBORDERS OF THE ARANEIISTA 



i. With 4 slits into lung sac [Tetrapneumones]. Che- 

 lifer claw directed downward ; 8 closely grouped 



eyes Territelar!' 



(Tunnel-weavers) 



a*. 2 slits into lung sac [Dipneum ones]. Chelifer claw 

 directed inward. 



i a/cct/n, mite. 2 Fig. 93. 



