200 SOME MINOR PROBLEMS CONCERNED IN THE LOCAL 



and their possibilities great, it does not follow that they are always 

 successful. A few illustrations may be quoted. In the Chelmer at 

 Felstead, at a certain place there grow Yellow Water-lilies and a 

 species of large Rush. These have retained their situation for more 

 than thirty years ; but they have made no progress either up or down 

 stream during that time, thus showing that, although they have flow- 

 ing water agency continually at hand, they certainly do not always 

 use it. In careful and long-continued examination of the floating 

 debris of the river at flood time, I have found but very few seeds of 

 any kind. In the river silt, which is periodically removed from the 

 bed of the river here, seeds are also .rare. Those occurring most 

 frequently (indeed I do not remember to have observed others) 

 are Bistort, Comfry, and Teasel, inhabitants of the river's bank. 



In The Essex Naturalist (vol. vi., page 76), mention is made 

 of the Water Soldier [Stratiotes) as being an inhabitant of a certain 

 pond at Saling during the last fifty years. None of the various 

 agencies for seed dispersal appear to have been brought into play 

 in that case for a very long time. Near Leighs Priory, there grows 

 a variety of Oak with curiously gnarled branches, some specimens of 

 which must be from two to three hundred years old. I do not 

 remember to have seen any trees with exactly their peculiarity further 

 than about a mile from that centre, and should say that all now 

 living are connected by de3cent. If that be the case, we must put 

 the acorn down as sometimes a slow traveller. Some field crops, 

 (clovers, etc.) of fifty years' standing, have not yet succeeded in 

 establishing themselves by the wayside. Many more instances 

 might be quoted of this partial or slow distribution, which is 

 perhaps connected especially with those plants the seeds of which 

 have no special adaptation for diffusion. In those plants having a 

 feathery pappus, and eminently adapted for wind-agency, the 

 opposite state obtains, they being widely and equally diffused. 

 This is well illustrated by the growth of thistles this year, which 

 are to be found in meadows and fields alike, a vast multitude. 



This incalculable element of diffusion is still further complicated 

 by curious anomalies. Some plants do not even produce ripe seeds, 

 but depend upon certain other offshoots for the perpetuation of their 

 species. This obviously excludes some of the agencies for their 

 diffusion, and would, one would think, tend to their extinction. 

 The Horse-radish {Cochlearin armoracia) belongs to this class. A 

 cottage garden here was ploughed up many years ago, in which was 



