IT PREFACE. 



my Father, T was induced many years ago, to pay attention to 

 it.* After striving ineffectually for many years, to refer the 

 plants we gathered, to species already described as British, or to 

 make them agree with the characters published in our botanical 

 works, we became fully persuaded that the entire genus required 

 revision, and that the only way to arrive at the truth was by 

 taking nothing for granted, and by examining the specific claim 

 of every specimen. This led to the collection of a considerable 

 series of examples, especially from our mountain districts, which 

 quickly afforded an insight into the great range of form that 

 many species presented. We therefore collected roots of all the 

 forms of every species which we met with, that had any appearance 

 of distinctness ; believing that if cultivated in the same soil, and 

 having all the surrounding circumstances removed which con- 

 tributed to make them vary in their wild state, we should find 

 that many would lose their apparent differences, while others 

 would remain permanently distinct, or perhaps exhibit characters 

 still more clearly distinguishing them from their nearest allies. 

 The result was as anticipated; many plants differing widely in 

 appearance originally, approximated so closely under cultivation 

 as to be clearly identical j while others, which when wild bore a 

 strong resemblance to each other, exhibited, under these cu-cum- 

 stances, well marked and permanent characters. Others again 

 retained some yew distinct features, and yet so closely approached 

 the typical form in the leading points, as apparently to have only 

 a claim to the name of varieties. Many plants hitherto regarded 

 as varieties, belong to the first of these classes ; being only extreme 



* This commeneed dining a botanical tour in Teeadale in 1842, in company 

 ■with our fiiends Charles C. Babington, and the late Jamea Edward Winter- 

 bottom, and when Eieracium iricum was first detected as a native of England, in 

 a wild basaltic gorge of CronHey Scar. 



