WATER-MITES AND THE WATER-BEAR. 263 



will probably be very irregular I know mine is but it 

 will answer every purpose. The mite is placed in this 

 cell, and a thin cover applied to the opposite side, thus 

 forming a glass box that can be turned over for the ex- 

 amination of both surfaces of the animal, and is deep 

 enough not to injure the soft body, yet shallow enough 

 to restrain its movements. 



The mouth of the mite is usually a complicated affair, 

 and is sometimes surrounded by a circular elevation or 

 ring called a hood, and always having short, jointed 

 palpi, or feelers. At some distance back of the mouth, 

 in some forms quite near to the posterior border, but 

 always in the median line, will be seen in the female 

 mites a small dark spot or narrow line which is really 

 an opening. In some this orifice, which may be called 

 the ventral opening, is covered and concealed by a large 

 plate, called the ventral plate ; or there may be two 

 plates, curved, oval, or other shape, one on each side of 

 the ventral opening. They are useful to the naturalist 

 as one means by which the mites may be classified, and 

 they should be carefully searched for by the beginner 

 who desires to learn the name of his specimen. They 

 are not present in the males. The reader will therefore 

 perceive that to identify his captive the specimen must 

 be a female. The two sexes, however, differ so con- 

 spicuously in appearance that they are easily recognized. 

 The female always has the posterior border of the body 

 more or less evenly rounded, while the male frequently 

 possesses a peculiar little tail -like process projecting 



