CLIMBING PLANTS. 355 



— The fibres of which they are composed grow spiral, and in the same 

 manner they turn. 



The dingers are also a large class. The Vine may be given as an 

 instance ; its tendrils move in all directions in search of a hold, and 

 when got they cling round it, and in any direction. The Passion- 

 flower is of this class. 



The Virginia- creeper may be given as an instance of both climbing 

 and clinging. It is curious to observe this plant clapping its tendrils 

 to the wall ; then they become broad at this part, and stick by a kind 

 of suction, or attraction of cohesion ; or they will insinuate themselves 

 into holes or crevices. It is curious to observe its tendrils always 

 inclining to the wall, although they may arise from the side of the stem 

 opposite to the wall. 



It would appear that weakness in anything that has powers of action 

 within itself, produces or stimulates the parts so weak to take all ad- 

 vantage of collateral support. Even a bean, which, when strong, seems 

 to depend entirely upon its own powers, yet if it grows weakly, as 

 when not in the sun, or [from] any other cause acting to hinder 

 strength when growing, — in such, if a stick is put into the ground close 

 by it, it will twine around it in loose spiral turns 1 . 



1 [The following, in answer to inquiries by Hunter, is in the handwriting of the 

 celebrated pupil of Linnaeus, Daniel Charles Solander, M.D., the companion of 

 Banks in the circuninavigatory voyage of Captain Cook : — 



" Dear Sir, — I received your's, and have considered your Qs., which, as general 

 questions, are very easily answered : but when we come to particulars, to tell how 

 many have twining stalks, how many rooting stalks, and what number support 

 themselves by cirrhi or tendrils, how many by shutting up their leaves at night have 

 the appearance of sleep, which are affected by the touch, and how .many have self- 

 motion, — we shall find it very difficult to ascertain the exact quantity even of the 

 plants that are known, both for want of observation and recollection. However, the 

 general answer is, that all the plants in which these different motions have been 

 observed, bear no proportion to the number of those in which we see nothing but 

 the common mode of vegetating and growing. Supposing there are 13,000 vege- 

 tables known, I cannot recollect above 773 out of that number which have any 

 particular motion. I have made a hasty calculation of these as follows, viz. — 



Somniferous plants 448 



Caule volubili 195 



Caule radicans [sic, in MS.] 16 



Foliis cirrhiferis 107 



Affected by the touch . 6 



Having self-motion 1 



773 



" This calculation can by no means be depended on as near the quantity that has 

 the different motions mentioned above ; there is no doubt a great number of plants 

 that sleep at night which have not been noticed ; and we shall, in all probability, by 

 observation find many that have self-motion, &c. On the whole, the different modes 



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