70 VIEWS OF THE MICROSCOPIC WORLD. 



embellish the cases in the different remaining varieties of the Lynceus. The 

 shell is perfectly transparent, and consists of a single piece without hinge or 

 joint ; being sufficiently elastic to permit the animal to open it at pleasure. The 

 position of the edges of the opening, is indicated in the figure, on the under side, 

 by the letter b. Not only is the animal itself protected by this delicate case, but it 

 affords a secure retreat for the young when danger is near. They then escape 

 from the approaching peril by swimming within the shell of the parent, which 

 the latter opens for their reception, and closes as soon as their entrance is effected. 

 The two eyes of the Lynceus at d are of different sizes and are of a deep black 

 hue ; while the rest of the animal is buff, approaching to orange. The beak is 

 seen at c, and the two horns or feelers at g. Within the shell is a row of four 

 false feet, easily discerned, that assist the Lynceus in creeping along the stalks 

 of plants, to which it attaches itself by pressing their sides with the edges of its 

 shell in the manner of a pair of pincers. These members also subserve another 

 purpose, causing the animal, as it advances through the water, to proceed with 

 a revolving motion ; in which action it is also aided by the appendage /, which, 

 striking against the water like a fin, renders the rotatory motion of the Lynceus 

 more rapid. This organ, which resembles a tail, is armed with two strong 

 claws, is forked at the extremity, and fringed along the edges with rows of hairs. 

 The Lynceus feeds on animalcules, and is the food of larger water insects. The 

 position of the stomach is indicated in the drawing by the curved figure within 

 the shell. 



THE SMALL WATER-FLEA. This little animal is found abundantly in ponds 

 and brooks during the summer months, sporting about in the waters with great 

 activity. According to Pritchard, they are usually colorless in ponds covered 

 with herbage, but in small collections of rain water in a loamy soil they glow 

 with a fine bright red hue. A drawing of this animal, of its real size, is seen in 

 figure 102, and a magnified representation in figure 103. The body of the 

 W'ater-flea is covered with a kind of armor, formed of plates of shell that over- 

 lap each other, and are capable of being moved sideways as well as up and down. 



Their ends do not meet on the underside, thus affording a sufficient space for the 

 insertion and motion of the organs of respiration, which are seen at a, but are 

 exhibited with greater distinctness ^ c, where they are more highly magnified. 



The eye of the Water-flea, show at of, is of a dark crimson hue, and from 

 each side of it, spring two pairs of horns, which consist of numerous joints, 

 studded with bristles, two or more proceeding from each joint. 



In some species the sexes are distinguished by them, the males having a bulb 

 about the middle of the right antennae, or horns, as shown in figure 104. The 

 appendages which are seen attached to the lower extremity of the animal are 

 the bags containing its eggs, and which are together, nearly equal in size to the 

 bulk of the insect itself. Below these sacks the tail is forked and adorned with 

 a plume of fringed hair. In most instances the shell of the Water-flea is trans-, 

 parent like crystal, but it is frequently embellished with beautiful tints. Some 



