2.2 



The Scottish Naturalist. 



Botany itself is an enormous kingdom ; and it is most fortunate 

 that gentlemen of high abilities and education and attainments 

 should devote their attention to this particular branch of the 

 science. 



WING to the great extent of old shady woods in the neigh- 



\J bourhood of Inveraray the lichen-flora is unusually 

 luxuriant. The number of species is perhaps not so great as in 

 many localities more open to sun and wind : but the size of the 

 individual specimens is very remarkable. Nowhere else in Scot- 

 land is there such a predominance of the largest foliaceous 

 species ; and their presence seems to have prevented the growth 

 of the smaller crustaceous kinds. 



The most common and conspicuous form is the Ricasolia 

 amplissima, which is the largest of the British lichens, remind- 

 ing one by the thickness and wide-spreading dimensions of its 

 lobes, more of tropical than of northern species. At Inveraray it 

 grows on almost every tree, being quite indiscriminate in its choice 

 of a habitat. It covers the trunks, of the old beeches especially, 

 from head to foot with its vegetable cuirasses. It is found very 

 frequently in full fructification ; while in other cases the centre of 

 the thallus is covered with large clusters of the dark olive-green 

 glomules, that are so peculiar to this species, and that serve as a 

 secondary fructification to propagate the plant, when the norma ^ 

 apothecia are absent. In dry weather this lichen is of a greyish white 

 colour; but under rain it assumes a vivid green hue, which con- 

 trasts beautifully with the reddish-brown apothecia, and with the 

 snow-white under surface. 



It is curious how certain forms of lichens that are extremely rare 

 or absent altogether in most localities become the commonest 

 species in certain places. With us Parmelia saxatilis covers 

 almost every boulder and tree ; but in the south of Europe, 

 particularly along the Riviera, it is one of the rarest forms, and 

 P. caperata, which with us is very local and uncommon, takes its 

 place and becomes the common lichen of the country. With us 



THE LICHENS OP INYERAKAY- 



By Rev. Hugh Macmillan, D.D., LL.D., F.R.S.E. 



