WATEE-SPIDEKS AND WATER-WORMS. 277 



it is closely allied. It is not only found in ponds and pools, 

 but also in the Thames and other rivers. 



River "Worms are exceedingly prolific and very gregarions. 

 As they breed so quickly, they are useful in supplying fish 

 and other carnivorous animals with excellent food. These 

 Worms are often sold by aquarium-dealers, at so much a mass 

 of them. But as they quietly die, unless properly treated, a 

 little care is necessary in buying them, or else the purchaser 

 will perhaps find that he has bought many dead ones among 

 the living, and these will be sure to cause not a little 

 mischief if introduced into the tank. The dead "Worms 

 may be detected by their being of a lighter colour than those 

 which are alive and healthy, and by the unpleasant smell 

 which will most likely proceed from them. It is prudent to 

 refuse to buy any "Worms, if all do not seem to be alive and well, 

 for it is a difficult matter to separate the living from the dead. 

 In shops these "Worms are generally kept in rmming water, or 

 in that which, is frequently changed; or in a running stream 

 during the night, and out of water altogether, but covered 

 with a wet cloth, during the day. But I find from experience 

 that they will not live in health for long under any one of 

 these conditions, though perhaps long enough to answer the 

 dealer's purpose. It is not natural for these "Worms to be 

 kept iu tangled masses, either in water or out. Of course, the 

 condition most conducive to their health while in confine- 

 ment, is that which is most similar to that out of which they 

 were taken; this may be attained by placing them ia soft 

 mud, over which there is water to a depth of from 2in. to 

 4in. They m.ust not be too crowded. "When the "Worms are 

 required for the aquarium, a small quantity of mud con- 

 taining a number of the animals may be taken by the help 

 of a small hand-net and placed iu a shallow vessel, such as 

 an old soup-plate. The mud, which has been placed with the 

 "Worms in the plate or other receptacle, should then be washed 

 away with a stream of water made to run from a pump, tap, 

 or siphon. The current of water should be strong enough 

 to remove the mud, but not so great as to carry off the 

 "Worms. If the flow of water is carefully arranged, a small 



