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fitted for dissemination by this agency. Such fruits are those of narrow- 
leaved dock, showing a round, rough, spongy growth on the outside of each 
of the close fitting, persistent sepals; of the Asa-Gray sedge, with its in- 
flated sack attached to the fruit; of the arrowhead, with its corky margined 
fruits which are able to float on the water. 
Black-seeded Plantain 
The seeds or fruits of many weeds are in one way or another carried 
by animals. Thus when slightly moist, the seeds of peppergrass, plaintain, 
groundsel, dropseed grass, and many others, are sticky and will adhere to 
animals’ feet or covering. Some sedges, chickweeds and catchflys have 
sticky glands, by means of which they cling to passing objects. The fruits 
of the avens, and the burs of the common burdock, are armed with hooks, 
and the fruits of the bidens or beggar’s ticks with spines, by means of which 
