154 Floristik und Systematik der Phanerogamen. 



Woods. The natural woods of oak and birch are chiefly confined 

 to the sheltered Valleys; their upper limit is 900 feet on the western side 

 of the Penn in es, and 1500 feet on the eastern side. There is evi- 

 dence from remains in the peat that an extensive birch forest or scrub 

 extended up nearly to the summits of the higher hüls; the author esti- 

 mates that in Parts I and 11 (560 sq. miles);, forest formerly covered 

 about 140 sq. miles, vvheras at the present day it Covers only 11 sq. 

 miles. Plantations of Piniis sylvestris occur up to 1770 feet altitude, but 

 remains of this tree were found in the peat up to 2400 feet on Gross Teil. 

 Spruce (Picea excelsa) has also been planted in the area. One wood 

 attains to over 20U0 feet, and this in its upper part is made up of wind- 

 swept Spruce and Larch from 2 to 4 feet high, recalling the tree-growth 

 in Northern Europe and Siberia. 



Sup-alpine Moorland. The maps are coloured to show : 1. Natural 

 Pasture, 2. Grass Heath of grasses with heath plants, 3. Grass Heath with 

 Eriopliorum, 4. Grass Heath with Calluna, 5. Grass Heath with Vacci- 

 nium, 6. Heather (Calluna Erica), 7. Heather with Eriophorum, 8. Cotton- 

 grass Bog (Eriophorum). The colours for 2. and 4. occupy the largest 

 area. The Grass heath occurs in two extreme forms: a) Nardus stricta 

 grass heath on steep dry slopes nearly free from peat, and b) Molinia 

 varia grass heath on wet peat-covered ground and in hollows. Lists 

 of the associate plants are given. Intermediate types are produced by 

 Vaccinium Myrtillus, Calluna Erica, Deschampsia flexnosa, and Juncus 

 squarrosus becoming more or less dominant in the Nardus heath. The 

 Molinia heath may be mixed with^ or entirely replaced locally, by Erio- 

 phorum vaginatum and Deschampsia caespitosa. The upper limit of the 

 grass heath and the lower limit of the heather formation coincide as a 

 rule with the transition from limestone to shale beds. The heather moor 

 forms a zone at a higher altitude than the grass heaths of the sub-alpine 

 region. The most extensive heather association consists almost enti- 

 rely of Calluna Erica and Eriophorum vaginatum ; it is developed on 

 the deepest peat;, often underlaid with a well-formed moor-pan. Towards 

 its lower limit this association passes over into Nardus gräss heath^ and 

 grass heath with Eriophorum, or on shallow well-drained peat into an 

 association of Calluna with dry-peat plants. 



Alpine Moorland, lying above 2000 feet. The maps show: 1. Vacci- 

 nium, 2. Vaccinium and Calluna, 3. Vaccinium with Calluna and Erio- 

 phorum, 4. Grass Heath with alpine plantS;, 5. Pasture with alpine plants, 

 6. Alpine plateau. The drier moors are distinguished by the abundance 

 of Vaccinium Myrtillus, V. Vitis Idaea and Calluna Erica. The wet 

 moors are similar to those already described in Part I, but there is an 

 increase in the proportion of Eriophorum vaginatum, E. angustifolium 

 and Rubns chamaemorus. The alpine grass heath is characterised_ by 

 Juncus squarrosus largely replacing the Nardus stricta of the sub-alpine. 

 On dry limestone and sandstone, Sesleria caerulea is the most abundant 

 grass of the alpine pasture. A list of alpine (arctic) species found in 

 the area is given. Exposed summits are covered chiefly with Raco- 

 mitrium lanuginosum, which forms mounds of peat. 



A feature of the author's work is the systematic examination of the 

 great peat deposits. In the present area, layers of Sphagnum peat fre- 

 quently occur at different levels in the same section, alternating with 

 layers containing Calluna, Empetrum, Vaccinium and Betula. At the 

 base of the peat, six species of arctic and alpine willows have been 

 found with other plant remains which suggest a former tundra condition; 

 this subject will be dealt with in a future paper. There has been much 

 denudation of peat, amounting in places to 20 or 30 feet, and this appears 

 to be due to natural agents, since it occurs in places where m.an has 

 not influenced these moors. At present Sphagnum is not a dominant 

 plant except in some localities, and the author believes that little peat is 

 being formed. The paper concludes with tables which give the number 

 of miles occupied by the chief types of Vegetation in Parts I and U. 

 The two papers by W. Lewis, and t!iose of Smith, Moss and 



