2 
INTRODUCTION. 
frequently the whole Lake District wears a dress 
of verdure and freshness when many other parts of 
England are parched and discoloured by long con¬ 
tinued drought. The dry heat, which is so prejudicial 
to fern growth, is thus avoided here, and a moderately 
warm, but at the same time moist, temperature, such 
as most of the British species delight in, is obtained. 
On the mountains again we find that those climatal 
conditions prevail which are requisite for the de¬ 
mands of the alpine and sub-alpine species. And such 
Ferns as the rare Woodsia ilvensis and Polystichum 
Lonchitis have been found in several places ; and even 
the still more rare Asplenium germanicum. Again, 
some rocks by the sea-side furnish a home for the 
Sea Spleenwort. It would be scarcely possible 
indeed to find anywhere more natural circumstances 
so happily blended together and combining to render 
the country an unexceptionable nursery for that 
tribe of plants which are consequently so abundant 
here, the Ferns. Ranges of lime stone mountains on 
the outskirts of our district produce in abundance the 
species peculiar to that formation. Slate, granite, 
and other rocks, rising to different heights and having 
different aspects, afford natural habitats for the 
numerous rupestral species, and those more delicate 
but graceful forms which are perhaps the most 
attractive of the Fern tribe and which revel in 
moisture and cool shade, have everything they can de¬ 
sire for their prosperity in the numerous peat bogs 
and the extensive leafy woods with which the district 
js so lavishly adorned. Of the forty-three species of 
