273 REVIEWS, {September, 



excursion, " as he will find them very comfortable to his toes, 

 after trudging a long day in heavy, hob-nailed shoes/' 



M. Crepin next discourses very sensibly about the prepara- 

 tion of the botanist's herbarium, without which no satisfactory 

 progress can be made in the pursuit. In drying succulent plants, 

 he appears to prefer a dry to a moist medium for destroying their 

 vitality. He recommends drying them in an oven. Many col- 

 lectors plunge them in boiling water for twenty or thirty seconds. 

 We have known this successfully accomplished by the application 

 of a mixture of naphtha and corrosive sublimate. But it requires 

 much practice and skilful manipulation to succeed in preserving 

 the colours of plants, and even to preserve the leaves of some of 

 the succulent species, such as the Sedums, Houseleek, etc. 



The botanical library of the young botanist constitutes the third 

 portion of the introduction to the Belgian Flora; and the lists 

 of works on the elementary principles of the science, on classifi- 

 cation, on descriptive botany, on the geography of plants, on pub- 

 lished collections of dried plants and figures (plates), are exten- 

 sive. On " geographic botanique," our author enters Professor 

 De Candolle's elaborate work and Jules Thurmann's ^Essai de 

 Phytostatique applique a la Chaiue du Jura et aux Contrees 

 voisines.' He does not notice our ^British Cybele.^ Possibly 

 he deems its information too local for general purposes. 



The fourth article is on the botanical geography of Belgium, 

 which M. Crepin divides into four regions, viz. : — 1. Region sep- 

 tentrionale, Region meridionale : these contain each two zones ; 

 the first, zone maritime, and zone campinienne ; the second, zone 

 argilo-sablonneuse, and zone calcareuse ; the third. Region arden- 

 naise ; the fourth. Region jurassique. The characteristic plants 

 of the northern regions and their four zones are common both 

 to Belgium and Great Britain, except Dianthus carthusianorum 

 and Arabis brassicceformis, — M. Crepin does not adopt Dr. 

 Smith's rule for the formation of similar compounds, as bras- 

 siceeformis, a rule strenuously recommended by a writer in 

 the ' Phytologist,' who, by the bye, does not always render im- 

 plicit obedience to it himself, — Sisymbrium austriacum, only a 

 straggler in England, Biscutella laevigata, Helianthemum pulveru- 

 lentum, Fragaria collina, Vincetoxicum officinale, Gentiana cru- 

 ciata, and G. germanica, — is this G. Amarella of British bo- 

 tanists ? — Digitalis lutea, Ajuga genevensis, Stachys recta, Stachys 



