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1. Alpina genuina embraces the larger portion of the forty odd 

 species or forms described in this work, more than half of which 

 are now published for the first time. Linnseus and other later 

 authors included several forms under the name H. alpinum, and it 

 is interesting to learn from Dr. Elfstrand that the plant described 

 by Backhouse under that name {Monogr. Brit. Hierae. p. 17, 1856) 

 is taken as the type species in Scandinavia, where it is of frequent 

 occurrence on the high mountains. 



2. Alpina nigrescentia. The author considers that the com- 

 monest and most representative species of this section, occurring in 

 Middle Scandinavia, are H. curvatum Elf. and H. atmtum Fr., 

 detailed descriptions of which are found in the treatise. Forms of 

 both these species have been found in Scotland. 



3. Alpina hyparctica differs from Alpina nigrescentia in having 

 floccose down on the margins of the inner and middle phyllaries, 

 and in having usually violet -spotted leaves ; this group is particu- 

 larly interesting to British botanists, because one of our plants 

 from the extreme North of Scotland has lately been identified as a 

 form of the Greenland species, H. hyparcticum Almq. 



The distinctive characters of alpina genuina, alpina nigrescentia, 

 and the isolated species, H. depilatum Almq., will be found in 

 Table I. at the end of the book. The characteristics of H. hyparctica 



Besides indicating the leading features of the groups into which 

 H. alpina Fr. may be divided, the author brings before our notice 

 two forms belonging to alpestria Fr., and others belonging to 

 vulgata Fr. The book ends with a full description of the true 

 M. nigrescens Willd., and three excellent tables for the determi- 

 nation of the species in this great division. In these tables the 

 specific characters are clearly defined, and by their use the somewhat 

 difficult task of distinguishing one plant from another is rendered 

 comparatively easy. 



The Introduction contains useful advice as to the best methods 

 of making observations on living plants. Certain essential characters 

 become so altered or lost during the process of drying, that care 

 should be taken to note them before the plant is pressed ; among 

 such points, for example, are the length, breadth, structure and 

 form of the involucre, the colours of the inner, middle, and outer 

 phyllaries, of the ligules, styles and stigmas, and whether the 

 ligules are ciliate or not. All observations should be made with 

 the aid of a lens, and not merely by the naked eye, on well- 

 developed, not old or dying, specimens. 



Dr. Elfstrand considers that sufficient importance has not 

 hitherto been paid to the nature and quality of the clothing of the 

 involucres ; he would note whether this consists of simple black or 

 white, curved or straight hairs, of white black-based hairs, of 

 black- or yellow-headed setse, &c. He lays special stress on a form 

 of clothing which does not appear to have been noticed or described 

 before, and to which he has given the name "microtrichs"; it 

 consists of a mass of extremely small, dense bristles, occurring on 

 the inner phyllaries of most of our Archieracia, but only to be dis- 

 tinguished by the aid of a powerful lens. 



