200 KANSAS ACADEMY OF SCIENCE. 



But not only have the seeds been taken to foreign countries, but 

 there has been a great exchange within our own borders. Plants not 

 known in one section of the land have been introduced and have be- 

 come acclimated. Railroads have been important agents in the dis- 

 semination of seeds. It is said that travelers have thrown seeds from 

 car-windows that have caused farmers untold inconvenience. 



Another means of transportation is by the lower animals. Some- 

 times the outer part of the fruit is fleshy and palatable, at times even 

 bright-colored and odorous, which attracts animals. The seeds them- 

 selves may be bitter and unsavory, or they are rendered indigestible 

 and are protected against the action of digestive juices by being en- 

 closed in a hard shell, or stone. In this way they are transported but 

 not destroyed. Examples of seeds of this sort are cherries, berries of 

 different kinds, grapes, currants, mountain- ash, and mistletoe. It is 

 from the glutinous berry of the last named that birdlime is raade.^ 

 "The berries are a favorite food of thrushes; and it has been sup- 

 posed that the mistletoe was propagated by the seeds deposited by 

 the birds ; the propagation is really by the wiping off of the seeds 

 from the bird's beak, which it rubs against the bark." "'Mistel' 

 (the 'mistletoe') is a diminutive of German 'mist' (dung), probably 

 in reference to the seeds deposited by the birds who eat the berries, 

 or it may refer to the slime of the berries."* 



Trees are annually planted by blue jays and other birds, as well as 

 by squirrels, which bury nuts and acorns in the ground, intending to 

 get them later, but fail to do so. 



Again, seeds are furnished with hooks or spines by which they ad- 

 here to the fleece or plumage of animals or to the clothing of man. 

 An example is Xanthium strumarium (common cockle-bur), which is 

 the well-known bur with two strong beaks at the apex that attaches 

 itself to the manes and tails of horses and mules, the wool of sheep, 

 and the hair of cattle, and is thereby transported to different places. 

 It is almost impossible to remove the burs without cutting off the 

 hair to which they are attached. We also see a wise provision of the 

 creator in allowing the bur-bearing plants to carry their fruit until 

 late in the season, thereby increasing their chances of dissemination. 



Other examples are the burdock {Arctium lappa L.), cleavers 

 {Galium verum L.), hound's-tongue {Cynoglossum officinale L.), 

 beggar's-lice {Eckinospermum virginicumlj^hm), and beggar-ticks 

 {Bidens frondosa L.), or Spanish needles {B. bipinnata L.), all of 

 which have the fruit enclosed in burs except Bidens frondosa L., 

 which has wedge-obovate akenes ciliate with upturned bristles, and is 

 two-awned, adhering to clothing only too readily. 



3. Gray's Structural and Systematic Botany, p. 469. 



4. Columbian Cyclopedia, art. "Mistletoe." 



