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KIDD'S OWN JOURNAL. 



or if the sun's rays be concentrated upon it by 

 means of a line, this leaflet immediately moves, 

 and also the one opposite to it ; both bringing their 

 upper surfaces into contact, and at the same time 

 inclining forwards or towards the extremity of the 

 small petiole on which they are seated. Then other 

 pairs of leaflets, nearest to that pair first touched, 

 close one after the other in a similar manner ; and 

 next the partial petioles fold together by inclining 

 upwards and forwards ; after which the common 

 petiole is affected, but it bends downwards, having 

 its point directed towards the ground ; that is, in 

 an opposite direction to that in which the previous 

 movements have been made. 



Many other plants possess this property of 

 taking on them extraordinary motions when any- 

 thing comes into contact with them. The object 

 effected by them all is, probably, to shake off slugs 

 and similar vermin. Among these other plants, 

 the leaves of which assume these contortions, are 

 species of Smithia and Biophytum ; and in Sene- 

 gal, a plant grows, called by the natives "how d'ye 

 do," on account of its performing a sort of salaam 

 or bow on being touched. 



In some species of plants the mere contact of 

 the air apparently seems sufficient to excite a 

 continual degree of spasmodic action, if the expres- 

 sion may be allowed, for the sake, probably, of pro- 

 tecting themselves from the depredations of insects. 

 There is, for example, the Desmodium gyrans, a 

 native of Bengal, where it is called Gora chand, 

 and which was brought into notice by the younger 

 Linnaeus. " No sooner," wrote he, "had the plants 

 which he raised from seed acquired their ternate 

 leaves, than they began to be in motion in every 

 direction : this movement did not cease during 

 the whole course of their vegetation, nor were 

 they observant of any time, order, or direction ; 

 one leaflet frequently revolved while the other on 

 the same petiole was quiescent, sometimes a few 

 leaflets only were in motion, then almost all of them 

 would be in a movement at once ; the whole plant 

 was very seldom agitated, and that only during 

 the first year of its growth, and was not at rest even 

 during the winter." Examples of this plant that 

 have been cultivated in our greenhouses, although 

 they have exhibited very well these strange 

 movements, have not been agitated so much as 

 when growing in their native country, or as those 

 brought thence by Linnseus. This is probably 

 owing to the careful culture of our gardeners, and 

 to the climate ; both of which preserve them from 

 the more active of their insect tormentors. Burnet, 

 who watched their movements in a glass conserva- 

 tory, made the rather remarkable discovery — that 

 although they might be temporarily restrained by 

 force, yet that when the restraint was removed, 

 they immediately moved about with increased 

 velocity, so as to make up for the time which they 

 had lost. Decandolle also observed them, and he 

 related that their leaves consist of three leaflets ; 

 two lateral, and one central and terminal. Their 

 movements, he describes, take place by little 

 starts, like those of the second-hand of a watch ; 

 and he further remarked that the one at one side 

 went up, so as to form an angle of about fifty 

 degrees over the level of the petiole, and the other 

 on the opposite side went down as much. This 

 process was then reversed, and repeated alter- 



nately. The terminal leaflet is also continually 

 inclined first to one side and then to the other. 



There is a natural family of plants principally 

 inhabiting tropical countries, and abounding at the 

 Cape of Good Hope, where they are objectionable 

 on account of the extremely fetid nature of the 

 odor of their flowers, examples of which are occa- 

 sionally cultivated here. The members of this 

 family afford very extraordinary instances of in- 

 stinctive movements. Plants belonging to it are 

 known from all others by having their pollen grain 

 contained in bags, from which their escape seems 

 almost impossible. However, when the time comes 

 for their seeds to be formed, a small tube grows 

 from each pollen grain ; and these tubes all direct 

 themselves towards a thin spot of the bag which 

 holds them. This they pierce, and then direct 

 themselves towards the stigma. To effect this 

 object they have sometimes to ascend, sometimes 

 to descend, and at other times to proceed outwards 

 at right angles ; but they invariably hit the exact 

 direction, according to the position of the flower, 

 and arrive at the stigma ; thus the seed is fer- 

 tilised. 



A plant grows wild in Carolina called the 

 Diono&a muscipula, or Venus's fly-trap. "The 

 leaves of this," says Henslow," consist of a flattened 

 petiole, at the extremity of which are two fleshy 

 lobes, which lie, when expanded, in the same plane 

 with the petiole. These lobes are capable of being 

 elevated and brought together into a position per- 

 pendicular to the surface of the petiole. They 

 are furnished with cilia, or bristles, round their 

 margins, which stand nearly at right angles to 

 their upper surface ; and there are, besides these, 

 three little short bristles placed upon the upper 

 surface of each lobe in a triangular order. W hen 

 a fly or other insect, crawling over the surface of 

 the lobes, touches either of these latter bristles, 

 the irritability is excited, the lobes suddenly close, 

 and the insect is imprisoned like a rat in a common 

 gin. Some little time after the death of the 

 insect, the lobes unfold, and wait for another 

 victim." 



It appears probable that the plant makes use of 

 the fly, although it is difficult to conceive in what 

 manner. Mr. Knight experimented upon a num- 

 ber of these plants, all of which were placed so 

 that no insects could get at them. He furnished 

 the leaves of some with scraped beef, leaving the 

 others without any such provision ; and he found 

 that the plants supplied with the beef flourished 

 more than the others. 



We possess in this country three species of 

 Drosera, or sun-dew ; all of which exhibit similar 

 instinctive movements, the result of which is to 

 catch insects. The upper surface of their leaves 

 is furnished with long hairs, which terminate in 

 glandular and viscid globules. An insect alighting 

 upon them first gets entangled in the viscid matter, 

 and then the hairs begin to move in, close upon it, 

 and hold it until it is dead. 



But perhaps the most extraordinary of the fly- 

 catching plants is the one described (somewhat 

 obscurely) by Mr. Drummond, who found it in the 

 Swan River colony. The lower lip of the flower 

 of it, he states, is a boat-shaped box, in which the 

 anthers are situated; and the upper one, which he 

 thinks is a stigma, forms a door or lid which exactly 

 fits it. The hinge upon which this lid moves 



