family of pinks 157 



Flora of the Shingle Fans. 



The range of mountains known as the Southern Alps is a 

 very ancient one, and comparatively dry on its eastern slopes. 

 Consequently, there is not a sufficient amount of denudation 

 to carry off to lower levels, the broken rock formed by the 

 winter's frosts. Immense masses of detritus collect on the 

 eastern flanks, forming in many places great shingle fans, which 

 are thousands of feet in height. In these localities have been 

 developed certain highly specialized plants not to be found 

 elsewhere. One of these, Notothlaspi rosulatum, is elsewhere 

 described at some length, others are Stellaria Boughii, Cotula 

 atrata, Ligusticum carnosuluni, Craspedia alpina, Lobelia 

 Boughii. It is the first of these that we have now to deal 

 with. It grows at an altitude of from 4,000 ft. to 6,500 ft., 

 on the shingle slips in various parts of Canterbury and 

 Nelson. 



It is obvious that the ordinary chickweed of the garden 

 could not exist for long at such an altitude. Such a flaccid, 

 weak, prostrate plant would soon be broken and bruised by the 

 rain of shingle from above, or destroyed by the heat of summer 

 and the frosts of winter. For few, if any, plant habitats are so 

 subject to extremes of climate and the violence of storms, as 

 the shingle slip. In summer, the surface layers are dry, and 

 burning hot. In winter, they are wet, and even when not 

 covered by snow, icy cold. At a considerable depth below 

 the surface is a stream of water, often derived from melting 

 snow. At all seasons of the year, furious gales blow over the 

 unsheltered surfaces of the fans. In winter, the south-west 

 winds drive over them, laden with snow and sleet, and in 

 summer, they are swept by the no less furious, and sometimes 

 parching nor'-westers. Only a plant with a constitution of 

 surpassing hardiness and vigour can live under such rigorous- 

 conditions. One of the strangest features in connection with 

 them, is that they endure all these hardships with little or no 

 soil to feed upon. 



