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POND LIFE 



The word leech brings back memories of the good old times, 

 when the cure for all ills was blood-letting, and in those 

 beneficent days the worthy little creature, the medical leech, 

 was imported from the Continent, and spent the rest of its 

 life on British blood. 



Hirudo medicinalis, although the fact is not generally 

 known, is to be found in our country. It is about 3 inches 

 long, but is able to extend to 5 or 6 inches when it so wishes. 

 There are severa* British leeches, the most common being 



s. 



WORMS 



1. Gordius, conjugating. 2. Ophryotrocha puerilis. 3. Aelosoma. 4. Horse- 

 leech. 5. Hirudo medicinalis. 6. Young Clepsine. 7 Planarian. 8. Micro- 

 scopic worm. 



Aulastomum, the horse-leech. It is of a reddish colour, with 

 tranverse marking. Often fastened to a stone, Aulastomum 

 undulates in a very original manner, and continues this be- 

 haviour hour by hour. But it is only when swimming that 

 the horse-leech is really at its best. Lengthening out into 

 a thin ribbon, it swims by most graceful undulations. When 

 not in such a hurry the leech wanders by dragging itself along 

 by means of its sucking discs (looping). 



Every stream contains leeches, but in some districts they 

 are much more common than in others. The general appear- 



