Nm). 28, 1889] 



NATURE 



effort that was ever made to represent things as they 

 are not. The two paragraphs on contorted strata and 

 inverted strata which follow are instances of the congestion 

 which is unavoidable in text-books of the second class. 

 It is impossible in so small a space to give the pro- 

 minence which it deserves to the conception of horizontal 

 thrust and compression, and very few readers would 

 realize, from the few words devoted to them, the sur- 

 prising character of the thrust-planes of the Scotch 

 Highlands. It is scarcely fair to magnetite to say that it 

 S07netiines exhibits magnetic properties, and ferrous 

 carbonate does not give a green, blue, grey, or purple 

 colour to rocks (p. 70). One and only one more objec- 

 tion will I urge. There is a lamentable absence of 

 geological sections. No verbal descriptions will suffice 

 to convey to anyone, let alone a beginner, clear notions of 

 the geological structure of a country without illustrative 

 sections. The reader of the present work will gather 

 from it the parts of the country in which the various 

 formations are seeji at the surface, but he will come away 

 with very few notions as to the lie of the rocks. I 

 cannot help feeling that the "imaginary scenes" during 

 the several geological epochs might be usefully replaced 

 by a set of geological sections. 



A. H. Green. 



THE FLORA OF DERBYSHIRE. 



A Contribution to the Flora of Derbyshire ; being an 

 Account of the Flowering Plants, Fertis, ajid Characecc 

 found in the County. By the Rev. W. H. Painter. 

 8vo, pp. 156, with a Map. (London : George Bell and 

 Sons, 1889.) 



DERBYSHIRE is much the most interesting of our 

 midland counties from a botanical and physico-geo- 

 graphical point of view. Geographical botanists, following 

 Watson, divide the surface of Britain into two regions of 

 climate — a lower or agrarian region, in which the cultiva- 

 tion of cereals and the potato is practicable, so far as 

 climate is concerned ; and an upper or Arctic region, in 

 which no cultivation is possible. The agrarian region is 

 divided into three zones, and whilst in Surrey, Hamp- 

 shire, Wiltshire, and Kent, only one of these three zones 

 is represented, in Derbyshire, Shropshire, and Cheshire, 

 we get all three of them, and a greater area of super- 

 agrarian zone in Derbyshire than in any other midland 

 county. The plants of Britain, botanical geographers 

 divide into two principal groups — the southern types, 

 which have their head-quarters in Central Europe, and 

 the boreal types, which have their head-quarters in 

 Northern Europe, and grow only upon high mountains 

 further south. The southern types are to the northern as 

 six to one — about 1200 species against 200 ; tit less than 

 50 species reach the midland counties. In Derbyshire we 

 get a declination of surface from mountains nearly 2000 

 feet high down to a low level, so that it shows better than 

 any other county how, in the centre of England, the 

 boreal and austral elements of the flora meet and mingle 

 together. 



The whole area of the county is a little over a thousand 

 square miles— about one-sixth that of Yorkshire. The 

 Pennine chain, the backbone mountain-ridge of the north 

 of England, extends for some distance into Derbyshire 



forming the watershed between the streams that flow into 

 the German Ocean and the Irish Channel. We may 

 divide the county into two unequal halves by a line that 

 runs across it from west to east, from Ashbourne to Duffield. 

 South of this line, with Derby in its centre, is a level 

 tract underlaid, by new red sandstone, with a flora like 

 that of Leicestershire, Nottinghamshire, and Warwick- 

 shire. North of this line, all the rocks are Palaeozoic, and 

 the level gradually rises. The Carboniferous limestone 

 occupies the lower levels about Castleton, Matlock, and 

 Buxton. This is much the most interesting part of the 

 county, and the best known to strangers, the region of 

 lead mines, caverns, and romantic narrow dales, girdled 

 by high cliffs of limestone : Miller's Dale, Monsal Dale> 

 Ashwood Dale, Chee Tor, Chatsworth, Haddon Hall, 

 are all familiar names aUke to botanists and lovers of 

 fine scenery ; and Dovedale, Bakewell, and Rowsley are 

 classic ground to anglers. The market-place at Buxton 

 is over 1000 feet above sea-level, so that Buxton is on 

 a par, so far as plants go, with Dundee or Aberdeen. 

 The heights of Abraham, over Matlock, are about the 

 same height above sea-level as the town of Buxton. 

 About Castleton and Buxton the limestone reaches a 

 height of 400 or 450 yards, and with it many plants of 

 the lowlands ; for instance, Epilobiuin hirsututn, Galium 

 cruciatuni, G. 7'eruin, Lamiuiii picrpurewn, and L 

 inctsttvi, reach a higher level than anywhere else in the 

 country. On the whole, the botany of the Derbyshire 

 limestone tract is most like that of Ribblesdale, Aire- 

 dale, and Wensleydale. Above the limestone in the 

 Peak country, and around Buxton and Castleton, there is 

 a considerable thickness of shale and millstone grit. The 

 flora of these higher levels is poor and monotonous, but 

 we get the cloudberry {Rubus Chamamorus) on Axe-edge, 

 the bearberry {Arctost.iphylos Uva-ursi) on the moors 

 round the head of the Derwent, and the whortleberry 

 {Vaccinium Vitis-idced) in several places about Buxton and 

 Glossop. East of all these is an area of coal- measure 

 country, the flora of which seems to be very poor, and to 

 resemble that of the country round Huddersfield, Shef- 

 field, and Halifax. 



Mr. Bagnall has already shown, in the Journal of 

 Botany, that Mr. Painter's numerical analysis, on p. 4 

 of the " Derbyshire Plants," classed under their types of 

 distribution, needs material revision. Out of 532 plants 

 universal in Britain, j\Ir. Bagnall's estimate, founded on 

 Mr. Painter's detailed list of species, is 486 species for 

 Derbyshire. In all probability, most of the other 46 

 species will be found if they are carefully sought ; but, 

 of the 599 species which represent the characteristic- 

 ally southern element in the British flora, there are 238 

 species in Derbyshire, or less than half I cannot under- 

 stand why the figure of the Germanic, or characteristic- 

 ally south-eastern plants, which is 127 for Britain as a 

 whole, 38 for North Yorkshire, 26 for Northumberland 

 and Durham, should be as low as 14 for Derbyshire. 

 Out of 201 boreal British species, there are 39 in Derby- 

 shire against 104 for the Lakes, 93 for Northumberland 

 and Durham, and 76 for North Yorkshire. What Watson 

 called the intermediate type, is a very interesting group ; 

 they are concentrated in the north of England, and I 

 suspect that the principal reason of this is, that they are 

 Montane plants with a preference for limestone. The 



