COMMON ELM G.N. 658! 



American Elm (heavy and hard: Pore-ring of two or more row 



vessels of the pore-ring of one row of vessels : rays generally visibl 



only: annual rings much reduced when dry, always so when wettei 



in width, rays scarcely visible even (transverse section), 

 when wetted). 



Mulberry (wood greenish- white Colour brown throughout thoug 



when freshly planed, the brown darker, on the surface : concentri 



colour being superficial : concentric lines present everywhere excep 



lines of Autumn pores developed in the inner Spring zone of ver 



only in the Autumn wood, if at all, wide rings. Silver-grain darke 



the vessels being for the most part than the fibres, 

 isolated. Silver-grain lighter than 

 the fibres). 



False Acacia [silver-grain and Rays dark brown. Parenchym 



rays in all sections, light-coloured. alternate (see Fig. 10). 

 Parenchyma in vertical section, in 

 palisade (see Fig. 12)]. 



Laburnum. As False Acacia, but As above : surface darkens bv 



surface darkens all over and the little and the silver-grain remaii 



silver-grain tends to become ob- prominent, 

 scure. 



WYCH ELM 

 Ulmus montana With: synonym, U. effusa Sibth., not Willd. Ulmace* 



A wood so much resembling that of the Common Elm that no di 

 tinction that is constant can be found. It is only by long practice thi 

 the two woods can be distinguished. The working qualities are the be 

 guide : the present species is troublesome to work, but easily riven. ] 

 developed rings sometimes have but one row of pores. 



(Note. Ulmus effusa is a bad species according to the Index Keicensi 

 U. montana was included by Linnaeus under the same title of U. cat 

 pestris.) 



The golden watery extract changes but little with perchloride of iro: 

 it does not turn inky. Spirally thickened fibres difficult to find. 



If our specimens be characteristic, then the points to be looked f 

 are the less-pronounced half-tone effect produced by the rays in ta 

 gential section and (under the microscope) a corresponding differen 

 in the shape of the rays (see Figs. 10, 11). In U. mo-ntana, they are narrc 

 spindle-shaped bodies of a form which may be compared to the outli 

 of a racing skiff, while those of U. campestris are more like that of 

 steamer. The consequence of this difference of form is, that the rays 

 the latter species are more evident to the naked eye. 



The Wych Elm is hard to work, tough and elastic. U. campestris 

 much easier to work and though tenacious of nails is comparatively i 

 elastic. The appearance of some specimens of Wych Elm, suggests A 

 rather than Elm (the zigzag fringes of the latter of course, apart). 



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