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Tendrils exhibit irritability of the most highly developed form and 

 react to a number of stimuli by very rapid movements. 



When a tendril comes into contact with a branch of a tree or another 

 solid body, it will begin to curve in a time vaying from five seconds 

 to an hour, and soon completely encircles the body with which it has come 

 into contact. In this manner the apical growing portions of a vine are 

 fastened to a support. As soon as this has been accomplished the part 

 of the tendril between the plant and the object to which it is attached 

 exhibits another movement by which it is thrown into the form of a 

 spiral spring, which pulls the plant upward through a distance equal to 

 about one third the length of the tendi il. The tendril wall also move in 

 response to a number of other stimuli, such as heat, acids, electric cur- 

 rents, and may be rendered incapable of motion by ether or chloroform. 



A movement which has for its purpose the facilitation of reproduction 

 is offered by the Water Hyacinth (Eichhornia speciosa) which is to be 

 found in the botanic gardens of Jamaica. The perfection and germination 

 of the seed of this aquatic plant can take place under water only. If 

 an examination of the plant is made during the proper season it will be 

 seen that the showy azure flowers stand upon erect flower st dks several 

 inches above the water. Soon after the pollen has been conveyei from 

 the stamens to the pistils the flower stalk beg ns to bend downward 



