NOTICES OF BOOKS. 27 



which was the last work of Brongniart. Though grouped mto 

 many genera, and including a considerable number of species, 

 nothing is known of these save their beautifully preserved fruits. 



The great additions to our knowledge of the later Secondary 

 and the Tertiary Floras have enabled De Saporta to trace into these 

 periods many of the generic forms which constitute our cultivated 

 or useful trees. He adopts as a maxim, as if it could not be called 

 in question, that priority of existence means genetic paternity. 

 The great cause of the modification in the successive floras he finds 

 in the variations of the temperature. The centre of the distribu- 

 tion of our plants has been the pole, and as the ice advanced or 

 retreated, the vegetation had to accommodate itself to these vary- 

 ing conditions, and hence arose the forms preserved in the strata 

 or now living on the globe. But in the view of Saporta there is 

 much yet to be known ; he hopes, however, that one day we shall 

 be able to discover what is now unknown, and to withdraw the veil 

 which still hides from us the secret of the Itow of Creation. 



W. Caeruthers. 



Haandhufj i Ben Danske Flora. Af. Joh. Lange. Kjoebenhaven, 

 C. A. Eeitzels Forlag. 1886-88. 



This, the fourth edition of Dr. Lange's Flora, is a useful book 

 for British botanists, although it is of course written in the Danish 

 language. So many of our plants are to be found in Denmark, and 

 Dr. Lange gives so large a number of varieties, with careful references 

 to where the original descriptions may be found, with the synonymy 

 (so far as relates to Danish literature), that it would be a useful 

 work to compare our forms to see how far they agree or differ from 

 those of Denmark, the flora of which country holds a sort of middle 

 IDlace between that of Scandinavia and those of Holland and 

 Belgium. 



Arctic species are almost absent ; perhaps the nearest approach 

 to such are BuUiardia aqiiatica DC, and the two Carices, incurva 

 and jiaucijiora. Others of high latitudes are wanting, notably Curex 

 aquatilis Wahl., though one might reasonably have expected it to 

 occur ; is it really absent ? In Sweden it comes as far south as 

 Smiiland, but is not recorded from Scania, the province next to 

 Denmark. It discovery in Ireland (this year as far south as Kerry) 

 and Wales would point to the possibility of it as a Danish species ; 

 this is especially the case as to Ireland ; Wales may not be quite in 

 the same category, as its mountains may have formerly produced 

 the species, and its present habitat be only a remnant of a former 

 more plentiful occurrence. 



Dr. Lange gives a list of authors whose works are used or 

 quoted ; would this not be a useful addition to our Floras, of course 

 from the local point ? How useful to botanists far away from a 

 public library is the full list of Hartmann's Scandinavian Flora I 

 A list of local Danish botanists, one explanatory of terms used in 

 the book, and a remme of the Linnean and natural systems, are 

 followed by the Flora proper, consisting of 857 pages, with 15 pages 



