Reviews. 
3 6 4 
90 cm. (36 inches) at Pontresina, and 160 cm. (63 inches) at the 
Bernina Hospice—these being averages for five years. 
The average snow-limit of the district is given at 2,960 m. 
(9,710 feet). The highest larch ( Larix decidua) attains an altitude 
of 2,660 m. (8,730 feet), 1 and the highest Arolla pine ( Finns cembra) 
2,580 m. (8,470 feet). The average dwarf-tree limit is put at 
2,400 m. (7,870 feet), and the average tree-limit at from 2,200 to 
2,250 m. (7,220 to 7,380 feet). 
In addition to numerous excellent photographic illustrations 
of the vegetation, a beautiful coloured vegetation map accompanies 
the first volume, the colours being superimposed on the Swiss 
topographical map (1 :50,000). As is well-known, these Swiss 
maps are perhaps the best in the world, as regards clearness, 
physiographical detail, and contouring. The maps of the Peak 
District—even the six-inch maps—compare most unfavourably with 
those issued by the Swiss authorities; and as 1 have recently 
worked with the British ordnance maps of the Peak District l may 
claim to know their virtues and their shortcomings. 
Dr. RubePs map is constructed on rather different lines from 
British vegetation maps. British vegetation maps are fully 
coloured: Dr. RubePs map leaves the ice-covered areas and the 
boulder-covered areas uncoloured. However, as these areas are 
well depicted on the topographical maps themselves, there is no 
disadvantage in the plan adopted; and, besides, it materially 
reduces the cost of the map. Again, British maps reserve stippling 
for mixed or intermediate and transitional associations : Dr. Riibel 
uses stippling to indicate the chief forest trees. 1 am not convinced 
that this latter is the better course on the whole ; but it has the 
advantage of permitting the indication, on one and the same map, 
of both the forest-trees and the ground vegetation. 
The classification of the vegetation follows the well-known 
Swiss lines, as laid down by Professor Schroter. A number of 
“ vegetation types” are regarded as the primary divisions ; and these 
are successively divided into “formation groups,” “formations,” 
and “ associations.” The first four of the “ vegetation types ” are 
based largely on plant form, being (1) woods, (2) scrub, (3) tall herb 
ground (Hochstaudenflur), and (4) grass grounds (Grasfluren). 
The remaining “vegetation types” are determined more by habitat 
factors. The forest “formations” are dominated by (1) larch 
{Larix decidua), (2) Arolla pine ( Pinus cembra), and (3) Engadine 
pine {Pinus sylvestris var. engadinensis, Heer 3 ). 
These forest or woodland “ formations ” are scarcely the 
“ formations ” of British phytogeographers. In the Engadine one 
finds, generally speaking, a continuous forest on the lower mountain 
slopes: there is a great deal of mingling of the larches and Arolla 
pines; and the Scots (or Engadine) pine is very local. The ground 
vegetation of the three forest types varies. That of the larch forest 
on the newer and fresher soils, is grassy : that of the forest of 
1 The highest larch in Switzerland, according to Dr. M. Rikli, is in Valais, 
at 2,700 m. (8,840 feet). 
3 This variety is characterised by very short leaves, by the bark being red 
almost from top to bottom, by its yellow cones, and by its pointed crown. 
The habit of the tree allows a great deal of light to reach the ground. It is a 
very distinct-looking plant. 
