GUIDE TO TIMBERS OF NIGERIA 63 



grained. Shade of transverse section nearly similar to that 

 of the other sections. Would soil on account of the stickiness 

 of the surface. Smell, faint, but when wetted rather unpleasant, 

 recalling Elm. " Characteristic smell " (Volkens, I.e.). 



STRUCTURE. Distinctly resembles that of most Rutaceous 

 woods. 



Transverse section. (Prepared with broken glass.) 



Parenchyma of one kind only : (a] very narrowly sheathing 

 the pores and just visible from its colour as white points. 



Vessels not visible except by means of the P. (a), very small, 

 uniform in size, but diminishing in number outwards to the 

 ring- boundary, where they thin out considerably, becoming 

 widely isolated and leaving many empty spaces, 36-40 per 

 sq. mm. in the inner zone of the ring, 20-35 per sq. mm. in the 

 outer zone. Apparently all simple (i.e. no groups of pores) ; 

 shape, oval ; contents, red or sherry-coloured. Proportion of 

 the wood, very small. 



Rays just visible in the darker bands ; of one kind only ; 

 very evenly spaced ; slight variation in size, but with many 

 thin ends. There are about two to the tangential diameter of 

 a pore. Fairly straight, but with considerable amount of 

 taper ; 15-26 per mm. ; proportion of the wood about one- 

 third. 



Ground-tissue dense ; cells just visible with macroscope, 

 more on account of certain points which appear to indicate 

 crystals ; colour a beautiful golden-brown ; proportion of the 

 wood about one-half. 



Rings ill-defined to the unaided eye and still less definite, 

 when magnified, no certain boundary ; some dusky bands of 

 pigment here and there. 



Radial section.- Parenchyma (a) just visible with lens. 

 Vessels just visible to the naked eye as fine scratches ; contents, 

 white, opaque and amorphous, along with some globules of a 

 sherry-colour. 



Rays visible as very small flakes, by contrast of colour, 

 being darker than the ground. 



Tangential section as the radial, but the rays are minute lines 

 just visible with lens ; not in parallel ; height up to about 

 nineteen cells by one cell wide for the most part ; contents 

 abundant, the rays being filled with resin or gum, as indeed 



