19C7-1908] gg 



The lecturer commenced by stating that nutrition and 

 reproduction are the two great functions of plants, for by the 

 exercise of the former process the plant attains to maturity, its one 

 physical object being then the perpetuation of its species. As is 

 generally the case in organic nature, such an end is effected by 

 many and diverse methods, which in the vegetable kingdom 

 are roughly classified as vegetative reproduction and sexual 

 reproduction. Each parent plant aims to give its seedling 

 offspring the best possible chance of life by assuring it space 

 with a good supply of light and air. In many cases the 

 offspring would have no chance at all if they simply dropped 

 to the ground beneath the parent plant, and therefore divers 

 agencies are utilised by the plant to avoid this. Again, seeds are 

 in some cases dispersed without any special provision made for 

 the purpose, as when they are washed along in times of flood, or 

 being immersed in mud or adhering to the feet or feathers of 

 migratory birds. Darwin mentions a case when in a cupful of 

 mud from the edge of a pond he found no less than 537 plants 

 within six months. The mechanism of the dispersal of seeds may 

 be arranged under four heads — 1, ejection by the plant ; 2, 

 transport by air ; 3, transport by water ; 4, transport by animals. 

 Taking the water-borne fruits as the simplest of all cases, Mr. 

 Deane referred to a class of plants having small seeds which are 

 readily carried away by runnels of water — viz., those living in dry 

 or almost soil-less situations, clinging with difficulty to surfaces of 

 rocks, and, if not washed into crannies, speedily killed by drought. 

 Such is the Stonecrop, with its four little gaping fruits, which only 

 open when rain appears. After remarking on some interesting 

 examples of this, he passed on to the different adaptations for 

 dispersal by the plant's own means, where a large variety and 

 complexity of conditions are met with. Some plants produced 

 capsular fruits, thereby practising an economy of seed by only 

 opening partially and in dry weather ; then the passing breeze or 

 wandering animals may cause the seeds to be thrown out. The 



