WATE^-MITES AND THE WATER-BEAR. 29I 



7. Limn6chares (Fig. 198). 



This small mite may be recognized by its habit of 

 always walking. It never swims. In this it differs 

 from all the other known forms of fresh-water Hydra- 

 chnadae. The eyes are four, and are arranged on a 

 lanceolate plate (Fig. 198, much enlarged), two on each 

 side, with a central rounded projection between them 

 in front. They are also surrounded by hairs. The 

 coxae do not make the prominent elevations common 

 to other mites; but seem rather to be beneath the 

 cuticle. "The coxse of the anterior two pairs of legs 

 are closely approximate, as are also those of the two 

 posterior pairs, but the two groups are widely separ- 

 ated." The anterior are larger than the posterior. 

 The mites are small. 



If the observer should desire to make permanently 

 mounted slides of his specimens of mites, he may 'try 

 a preservative medium prepared by mixing eight parts 

 of water containing a drop or two of carbolic acid, with 

 one part of glycerine. This is said to keep the bodies 

 without the loss of their characteristic plumpness, nor 

 of much of their color, if mounted in a deep cell. Two 

 specimens should, if possible, be preserved in the same 

 cell, and so arranged as to show both surfaces. They 

 will usually need a large and deep ring. 



The fresh-water mites have never been systematically 

 studied by any American naturalist; there are, there- 

 fore, no books nor even isolated papers to which the 

 beginner may be referred for further aid. The field 

 is an entirely unexplored one so far as the water-mites 

 of this country are concerned. To a student with an 

 eye sensitive to color, and with a large amount of 

 patience, the subject should be an attractive one.. 



