FIELD BOOK OF PONDS AND STREAMS 



distributed common blood-suckers of shallow water (Fig. 119). 

 It conceals itself under stones, lying in wait for wading animals 

 which may come into the pool. It attacks fishes, frogs, turtles, 

 cattle, and man; it also eats larvae, worms, and great numbers 

 of frogs' eggs. 



It is dull green or olive green, with a row of about twenty red 

 spots through the middle of the back and a row of black spots 

 near each side ; the lower surface is reddish orange. This leech 

 is usually about half an inch wide and so flattened that the 

 edges of its body are sharp, not rounded as they are in the 

 horse-leech, Hcemopsis (Fig. 120). Length, 3-6 inches. 





Fig. 120. — Horse-leech, Hcemopsis marmoratis: i, 

 dorsal; 2, ventral. 



Horse-leech, Haemopsis marmoratis. — The horse-leech 

 (Fig. 120) lives in the mud by the sides of pools, ditches, and 

 streams, feeding on aquatic worms and mollusks; whenever it 

 has a chance it will suck blood from the legs of wading ani- 

 mals. Much larger related species occur in the lakes and ponds 

 of the northern states ; other species burrow in the mud. 



Its body is smooth and very soft ; the ground color is gener- 

 ally some shade of olive green, blotched with irregular spots of 

 lighter grays and darker browns and black. Length, 4 inches. 



Family Herpobdellidce 



Several genera and species of these worm leeches abound in 

 ponds and streams under stones and among plants where they 



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