428 Barry: Sylvan Vegetation of Fylingdales. 
circumstances. It is at once the inland section of the township, 
and also free, or nearly so, from glacial clays. Hence the 
presence in its slacks of birchwoods still existing and unmis- 
takable evidences that in times gone by these birchwoods were 
of considerable extent. 
The Alder (A/nus glutinosa Gaert.) calls for no remark. 
The Aspen (Populus tremula .).—Though rare, is 
nevertheless found here. The slacks of the moors or the 
moor edges are places in which I[ have seen it, so that it appears 
as essentially a highland tree ; and this, as far as I have been 
able to judge personally, is its character in Northern Europe as 
well asin Southern. Again, I have only seen it on the slopes of 
these slacks; never at the bottom by the becksides. Indeed 
the only specimens in the Ramsdale woods are on freestone 
rock with a south aspect, the situation being a clearing within 
a hundred yards of the moor, and the Aspen having sprung up 
since the clearing was made. This, again, agrees with what I 
have observed elsewhere. For though the authorities usually 
write of the Aspen as being essentially a wet soil tree, yet its 
constant occurrence in dry and rocky places (its stature there is 
naturally small) is one of the facts that has always struck me in 
the mountains of Norway, Scotland, and Corsica. On the slope 
facing east of Jugger Howe Gill the little woods or groves of 
primeeval aspect are, I think (for I have never climbed up to 
them), composed of this tree. There, however, I should say, 
the soil was humid. 
INDIGENOUS TREES, OF THE THIRD GEASS: 
The Rowan (Pyrus aucuparta Ehrh.), in contrast to the 
Birch, is one of the most ubiquitous and one of the most. 
impressible of trees. It does not seem particular as to either 
situation or soil. It springs up even on the sea cliffs of the 
Peak, and is part of the main undergrowth in the Oak woods 
of the dales. It accomodates itself to clays and to sour moor- 
land, as well as to its favourite rocks and rubble. Whenever 
a moor edge plantation is made, and has become tall enough to 
harbour birds, the Rowan is sure to appear, and in increasing 
numbers, owing to the voiding of its seed by wood pigeons 
and smaller birds. On pastured ground it is kept down, of 
course, by browsing ; but in rough enclosures, where there are 
neglected whin bushes, it often manages to make a_ show, 
thanks to the protection of those thorny thickets. In this way 
Naturalist, 
