ON SOME WATER PLANTS. 
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in colour, with bands of white spots, and are about the size of 
marbles. I confess that when I first pulled one up from the 
mud of a river-bed I thought for a moment I really had found 
a marble or china bead, through which the runner had grown. 
Arrowhead is abundant in England from Cumberland southward. 
fig 3. fig. 5. 
it is rare in Ireland and only naturalized in Scotland : it is found 
throughout Europe, North Asia and N. W. India. 
The Bulomus or Flowering Rush, often included in Alis- 
macea:, still flourishes in the Roding and gladdens our eyes 
with its umbels of pink flowers borne on long stems in mid summer; 
the narrow leaves, triangular in section, are all aerial. 
Another plant that often has ribbon-leaves is the smaller 
Bur-reed, Sparganium simplex. In the forest ponds, where it 
