A CURIOUS PARASITE. 177 



leafless species of LorantJms, consisting as it does 

 only of a very short stem, from which the crowded 

 flower-stalks form a dense cluster of bright-red, 

 moderately large flowers. Although it is not easy to 

 conjecture how it may act, it is conceivable that these 

 conformities may be results of natural selection ; but 

 it is also possible that, like many curious instances of 

 parallelism among the forms of plants belonging to 

 widely different types, the facts may hereafter be seen 

 to result from some yet undiscovered law regulating 

 the direction of variation in the development of 

 organic beings. 



In some places dense masses of spiny shrubs were 

 massed together, overgrown by climbing plants, 

 amongst which the most strange and attractive were 

 composites of the genus Mutisia. The Chilian species 

 have all stiff, leathery, undivided leaves ending in a 

 tendril, with large brownish-red or purple flowers, of 

 which very few were to be found at this advanced 

 season. Among the shrubs I was struck by a species 

 of Colletia, a genus characteristic of temperate South 

 America. They are nearly or quite leafless, and 

 remind one slightly of our European furze, but are 

 much more rigid, with fewer, but hard and penetrating 

 spines, which, unlike those of the furze, are true 

 branches, sharpened to a point and set on at right 

 angles to the stem. The species common here 

 {Colletia spinosa of Lamarck) grows to a height of 

 four or five feet, and would probably be found very 

 useful for hedges on dry stony ground in the south of 

 Europe. I regret that the seeds which I sent to Italy 

 have not germinated. 



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