The imm SOTEAUST: 



A Monthly Magazine of Natural History. 



Part 37. DECEMBEB, 1882. Vol. 4. 



THE DISSEMINATION 

 OF SEEDS. 



By J. P. SouTTER, Bishop Auckland. 



AMONGST the many marvellous 

 devices everywhere manifested 

 by Nature, for the preservation and 

 perpetuation of vegetable life, nothing, 

 perhaps, shows a happier adjustment 

 of means to an end than the numerous 

 exquisite contrivances for the disper- 

 sion of seeds. Every schoolboy is 

 familiar with the floating down of the 

 thistle, and elegant parachute of the 

 dandelion ; which, as he puffs away in 

 sportive play, and gleefully watches it 

 sailing along, he little thinks that his 

 tiny balloon as it wings its aerial flight, 

 is carrying with it the germ of the 

 future plant, which may haply fall on 

 suitable soil, where it may spring up 

 and blossom and bear fruit, to be simi- 

 larly transported. No wonder that 

 such like plants, with equally admir- 

 able migratory powers, should be so 

 widespread as to be well nigh ubi- 

 quitous. 



Annual plants, which perish as soon 

 as they have perfected their seeds, may 

 not be so absolutely dependent on this 



provision as those of perennial growth, 

 which persist through many years ; for 

 it is a well-known natural law that no 

 plant will grow and thrive well, under 

 the shade of another of the same 

 species. Hence the need for the seeds 

 to be carried to a distance. The pecu- 

 liar elements in the soil fitted for the 

 sustenance of one particular plant, also 

 becomes exhausted. It is obhged to seek 

 fresh fields and pastures new, therefore 

 we see a natural as well as an artificial 

 rotation of crops ; certain species thin 

 out and die off, whilst others take their 

 place without any apparent cause. 

 Others again finding a more congenial 

 habitat with favourable conditions for 

 dissemination rapidly over-run a whole 

 country, as witness the European 

 thistle, which has overspread im- 

 mense tracts in the arid plains of 

 South America, where it now forms 

 impenetrable thickets with its luxuriant 

 spiny growth. The rapidity of its 

 colonisation being aided as much by 

 the fleetness of its seeds as by the 

 robustness of its constitution. Al- 

 though the seed is the only part of the 

 plant which can be benefitted by these 



