ANIMAL LIFE IN PONDS & STREAMS 



the life-work of some scientists and they will afford 

 any microscopist, who is interested in them with 

 abundant occupation. 



Amongst the water weeds we shall probably find 

 another small but striking creature, known as the 

 sun animalcule, Actinophrys Sol. Why exactly it 

 is called the sun animalcule we cannot say, probably 

 it has earned its title from the fact that it resembles 

 the conventional idea of the sun, with light rays 

 radiating all round its circumference. The creature 

 is whitish-grey in colour, spherical in shape and just 

 visible to the naked eye. All over the surface of 

 its body there are a number of apparently empty 

 spaces, known as vacuole^ — they probably account 

 for its peculiar colour. Everywhere, it is studded 

 with long, slender-pointed rod-like outgrowths. 

 But rarely, the sun animalcule exhibits any move- 

 ment and for long periods the only signs that it is 

 living occur at feeding time. Its food consists of 

 water animals and plants, of varying size. When 

 a small animal comes into contact with one of the 

 pointed rods, which radiate from the animalcule, 

 it appears to be held there in some unaccountable 

 manner and, after a pause, it begins a fateful journey 

 by sliding down the rod to the spherical body of its 

 captor. Then it is passed into one of the vacuoles 

 and digestion very soon takes place. That it does 

 not do so immediately is shown by the fact that the 

 wheels of a wheel animalcule, which has been passed 

 to the vacuole of our subject, continue their move- 

 ments for a considerable period. When larger 



75 



