PALMACEjTS. 



25 



of the Passijlora, the Lily, and the Epilobium, incline against the stamens ; those 

 of the Tulip, the Martynia, and the Gratiola, dilate and become open in a very- 

 remarkable manner : the stigma of the Mimulus also opens, but, on the least 

 mechanical irritation, it again closes. The same movement may be observed 

 when the stigma has been recently separated from the style. 



The Stylidium presents a kind of excitable movement, which is also very 

 remarkable. This singular plant has the style joined its whole length with two 

 filaments of the stamens : the appearance of this column is unique, being termi- 

 nated by a glandular stigma surrounded by the four lobes of the two anthers. 

 In the young state of the flower, when the anthers are not opened, the column is 

 not excitable, but when the flower has arrived at perfection and the anthers are 

 open, the column is singularly irritable ; for on shaking the flower, or irritating 

 its column (which in its natural state is bent to one side of the corolla), it 

 instantly springs to the opposite side, from which after a certain time it returns 

 to its original position, and may be again excited in a similar manner. It is 

 found to be most sensitive when exposed to the rays of the sun. 



This movement of the stamens appears to be designed for the purpose of faci- 

 litating and effecting with certainty the discharge of the pollen from the anthers ; 

 and consequently to add to the number of causes which tend to ensure fecun- 

 dation. The stigma concurs in the same object, either by approaching the 

 anthers, or in dilating and offering a more extended surface for the reception of 

 the pollen. Such explanation however can scarcely apply to the Stylidium, the 

 anthers of which are already in contact with the stigma ; and no plant appears to 

 have less use for any particular precaution to ensure fecundation. Mr. Salisbury 

 suspects that the use of this movement is to drive away insects which may attempt 

 to insinuate themselves into the flower. Mr. Hensel has remarked that these 

 movements are under the influence of external circumstances : he states that if 

 the flower be made wet, the movement will not take place ; and if begun, it will 

 be interrupted. But in admitting the truth of this observation, it by no means 

 militates against the theory of excitable vitality. 



PALMACEiE. 



Among the various natural orders of plants, the Palmacece appear to stand 

 pre-eminent. Linnaeus, in the warmth of his admiration, called them the princes 

 of the vegetable kingdom ; and, assuredly, when we take into consideration the 

 grandeur of their towering, and generally simple stems, the beauty of the clus- 

 tered, and usually gigantic foliage, which crowns their summits, and the air of 

 magnificence with which they stamp the tropical landscape, they may with justice 

 be said to form a noble and distinguished family. But, independently of their 



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