106 DROPS OF WATER. 



and the eye is red. I have seen this species in 

 such numbers, that there appeared a perfect 

 swarm, though the water was obtained as late in 

 the year as October, their elegant form and 

 bright colours rendering it a beautiful sight. E. 

 pyrum is dark green, pear-shaped, and swims 

 rather swiftly. E. pleuronectes is like a small 

 green leaf with a short stalk : it is flat. E. lon- 

 gicauda has the power of twisting its body into 

 a spiral form, and is also somewhat leaf-shaped. 

 This is an elegant animalcule, the form very 

 curious, and the colour sparkling green ; the tail 

 is as long as the body, and, though colourless, 

 is very conspicuous. When two or three are 

 moving gently near each other, they form a very 

 pretty scene. E. acus has a slender body, with 



