IV.] VISCID SEEDS. 83 



parasitic on trees. Tlie fruits are eaten by birds, and 

 the droppings often therefore fall on the boughs ; but 

 if the seed was like that of most other plants it would 

 soon fall to the ground, and consequently perish. 

 Almost alone among those of English plants it is 

 extremely sticky, and thus adheres to the bark. 



I have already alluded to an allied genus, 

 Arceuthobium, parasitic on Junipers, which throws its 

 seeds to a distance of several feet. These also are 

 very viscid, or, to speak more correctly, are embedded 

 in a very viscid mucilage, so that if they come in 

 contact with the bark of a neighbouring tree they 

 stick to it. 



Dr. Watt has described a curious peculiarity in 

 another species of the same family. The fruit, like 

 that of the Mistletoe and of most other species of this 

 order, consists of a mass of viscid pulp surrounding 

 a single seed, and when detached from the parent 

 plant it adheres to whatever it may fall on. There it 

 germinates. The radicle when it has grown to about 

 an inch in length develops on its extremity a flattened 

 disc, and then curves about until the disc is applied to 

 some neighbouring object. If the spot to which the 

 disc has fastened is suitable, the development of the 

 plant proceeds there. If on the contrary the spot be not 

 suitable, the radicle straightens itself, tears the viscid 

 berry away from whatever it has adhered to, and 

 raises it in the air. The radicle then again curves, and 

 the berry is carried by it to another spot where it 

 again adheres. The disc then detaches itself, and by 

 the curving of the radicle is advanced to another spot 

 where it again fixes itself. Dr. Watt says he has seen 



G 2 



