416 Relations betweeri Geological Strata and 



Near the river Doon in Ayrshire, especially, its size was such 

 as to incline me to examine it as a new species. Throughout 

 Ayrshire this is one of the most fertile plants. 



Geranium pratense (crowfoot crane's-bill) is, I am per- 

 suaded, to be found luxuriant only in basaltic districts. Every 

 istream in Ayrshire, and to the east of Glasgow, is rendered 

 eminently beautiful by the rich azure of its transparent petals, 

 and the singular verdure of its long peltate leaf. The Clyde, 

 the Calder, the Tannock, and every streamlet near Bothwell 

 and Campsie Fells, possesses this flower. The bed of these 

 rivers is basaltic. 



In Ayrshire, the Ayr *, the Marnock, the Doon, the Irvine, 

 and the Garnock have tufts of this plant on their banks, from 

 the source to the sea. Long before botany became a study, 

 these flowers gave an interest to that country which is still 

 remembered with something of the quiet delight which an 

 early love of nature produces and perpetuates ; and even now, 

 after the contemplation of mere beauty in flowers has given 

 place to the pursuit of their scientific arrangement and philo- 

 sophical properties, there is a childish delight in the rencontre 

 of such mementos of early days, when time and thought and 

 pleasure were young and pure. I have met them, thus, in 

 southern counties, and occasionally near the Irwell ; but how 

 altered ! " Quantum mutati ab illis ! " f The hue is less 

 brilliant, the herbage weaker, the bed a few thin and scat- 

 tered patches. What can be the cause? Is it that later 

 impressions are warped by prejudice, from want of novelty 

 or of the requisite associations? Or does the preeminence 

 of Ayrshire crane's-bill depend on the position of the streams, 

 where it grows over basaltic rocks whose debris is more suited 

 to vegetation of this kind than the washings of the new red 

 sandstone of Lancashire ? The latter conclusion I am willing 

 to adopt, because it is the most reasonable ; and, if for no other 

 reason, because it favours my theory. 



Geranium lucidum belongs to lime, and seems not appro- 

 priate to basalt, Derbyshire abounds with this plant. I met 

 a most luxuriant crop of it near Warwick. It was there grow- 

 ing on a base of lime ; which was at considerable depth below 

 the surface. 



Erodium marinum I have seen only on Orme's Head, and at 

 Mount Edgecumbe, near Plymouth, where I found it on the 

 Devonshire marble, a rock very closely allied to the (Orme's 

 Head) mountain limestone. 



* This stream . occasionally crosses schist and plastic clay. In such 

 places this geranium is not found, 

 f " Ho\v difterent from those ! " 



