202 JUNCUS TENUIS WILLD. IN NORTH WALES. 



Harlech, and 3 miles from the sea, along a disused bye-road con- 

 necting the Harlech and Dinas roads. The locality is hilly, the 

 altitude being about GOO ft. above sea level. The rush is found in 

 isolated tufts in the beaten track running along the middle of the 

 road. In no case did I find any plants along the sides of the road 

 or in the neighbouring fields. The soil is loamy. It flourishes 

 well on an exposed part of the road, thirty to forty yards long, where 

 the soil is dry and thin. It attains a larger size in the more moist 

 parts of the road, but the tufts are fewer in number." These 

 habitats bear a curious and striking resemblance to those described 

 by Mr. Scully [Juurn. Bot. 1887, 335). In one case he says that 

 the plant grew "within a few yards of the sea, and quite near such 

 maritime plants as 0. distans, C. extensa, J. Geiardi; the latter 

 were within tidal influence, while J. tennis was just outside its 

 reach." This would exactly apply to the Portmadoc locality, 

 while the other habitat bears an equally striking resemblance to 

 the Harlech one, both being old grassy hill-roads. 



The conclusions that seem to present themselves from a study 

 of the Portmadoc and Prenteg localities are — 



1. That here at least the plant is undoubtedly a recent intro- 

 duction. It may of course have spread from a neighbouring 

 locality; when, however, we consider that indigenous plants which 

 are rare are generally in process of dying out, it seems far more 

 probable that a plant which spreads so readily as J. tenuis seems to 

 do is a recent introduction from a foreign country. 



2. Its strikingly erratic distribution and its disappearance as 

 soon as the grass is allowed to grow freely about it lend colour to 

 the view that it is not a native. 



3. The partiality of the plant for cattle-paths suggests that 

 cattle may be the means of distributing the seeds. The plant is 

 very probably a native of N. America. May not the seeds have 

 been carried over with cargoes of corn ? If so, we can easily under- 

 stand their becoming attached to the feet of cattle. Those that 

 happened to have dropped off in fairly open places would suc- 

 ceed in growing, while such as were left in the thick pasture 

 would be stifled by the herbage, or remain dormant until the grass 

 happened to be sufficiently trodden down to give them a chance of 

 growing. 



A study of the distribution of J. tenuis in other parts of the 

 world seems to confirm the view that it is a foreign introduction in 

 this country. As shown by Mr. Bennett, continental botanists are 

 much divided on this question. This uncertainty is in itself an 

 argument in favour of its not being indigenous. Buchenau, in his 

 monograph of the Juncacca [Kmjl. Bot. J<(hih. 1890, 193) says that 

 in Middle Europe it was formerly only known from a few localities, 

 but that within the last decade it has considerably extended itself. 

 These remarks are certainly significant. 



The distribution of the plant in America is strikingly different 

 from the above — 



1. It is one of the most common and best known, ranging from 

 the Peace Kiver through Mexico and the W. Indies to S. America 



