210 MR. A. W. HILL—REVISION OF 
4,720 m.). On El Misti, an isolated voleanie cone rising behind the town of Arequipa 
to a height of 19,200 feet, the snow-cap may be very small or may extend from 1,000- 
2.000 feet below the summit. Here N. turritella was found up to an altitude of 16,400 
feet (5,000 m.) and the species has a vertical range of 1,000 m. The highest record for 
any species of Nototriche is that; given by Fries for the plant collected by him on the 
Nevado de Chani, Argentina, in 24? S. lat. His species, which I have called N. Friesii, 
was found at an altitude of 5,600-5,700 m., and Dr. Fries informs me that these figures 
are correct. The altitude to which these plants can reach appears to be to some extent 
dependent on the snow-line, though they may be found sometimes in protected crevices 
above the line at which permanent snow usually occurs. In the Nevado de Chani the 
line of permanent snow lies at about 5,800—5,900 m., but on the Illimani-Illampu chain, 
owing to the greater collecting-area and to the presence of glaciers, the snow-line 
appears to be between 5,000-5,500 m., though Conway does not give exact figures. 
It seems somewhat surprising at first sight that the species reaching to the greatest 
altitudes should be found as far south as 24? S. lat., whilst those from Ecuador are 
found at lower elevations. The question is no doubt bound up with climatic conditions, 
and it is probable that the small rainfall and the small amount of permanent snow 
enable these plants to live at greater elevations in the southern districts. 
In the south the greatest height recorded is for a plant which has been described as 
a new species under the name of N. transandina. This was found by Gosse in the 
upper valleys of Aconcagua, about 32:5" S. lat., at 3,650 m., and appears to be identical 
with the specimen collected by Moseley on the Uspallata Pass in the same latitude. 
SOIL. 
With regard to the soil in which the Nototriches grow, very little information has 
been given by collectors. 
A considerable number of species, especially those of Southern Bolivia and Peru, 
flourish in voleanic ash. On the volcanie ash of El Misti and in the neighbourhood of 
Vincocaya, N. turritella (text-fig., p. 202), N. pedatiloba, N. Orbignyana, N. lanata, 
N. argyllioides, N. pedicularifolia, and N. sericea are to be found. XN. borussica, 
N. Meyeni, N. alternata, N. sajamensis also apparently flourish on the voleanic soil 
on the slopes of the mountains Tacora and Sajama. In such cases the plants form 
isolated patches or small cushions in the blackish-grey sandy ash, into which the roots 
penetrate to a considerable depth. 
According to Fries, the Nevado de Cháni, on which N. Friesii grows, is formed of 
granite, trachyte, and quartzite, the slopes being covered with stones, quartz, and sand, 
‘with a good deal of salt; and in the desert of Atacama, whence Philippi brought several 
species, the soil must be of a somewhat similar character. 
Weberbauer is careful to give particulars of the habitats of the plants he collected, 
and in most cases the soil is stated to be poor and stony. 
Speaking generally, it seems that the species with leaves of the palmatifid type prefer 
a poor dry soil, especially of a volcanic origin: it was noticeable, so far as I was able to 
observe on my own journey, that where a richer and deeper soil existed Nototriches were 
not to be found. 
