Xll INTRODUCTION. 



among GurriFER^ ; in Maodendron, Celastrus, and Lophopetalum among 

 CELASTRINE^} ; in Heynea, Amoora } and Wahura among MELIACE^ ; Cordia 

 in BORAGINE^J, and in other genera. The wood of the trees of the great 

 and important order of CONIFERS is always recognizable, at any rate, by 

 the constant character of the absence of pores ; that of the CUPULIFER^S 

 by the arrangement of the pores in wavy, radial lines, and a particular 

 texture; somewhat broad medullary rays often indicate the orders 

 DILLENIACE^E, E-HizopHoiiE^E, and MYRSiNE^B ; a close and even-grained 

 wood, most species of the great order of RUBIACEJR ; while the large 

 genus Ficus has its woods extremely uniform in character and recognized 

 by alternate layers of soft and firm tissue. 



In this way a little practice enables a very near guess to be made at 

 the scientific name of the tree which gave any wood which it may be 

 necessary to determine, and it may be hoped that, with a rather wider 

 acquaintance with the woods of India, we may be in a position to draw up 

 an analytical table for the woods which are most chiefly in use in India, 

 similar to that given at the end of the French Forest Flora. 



Mention has been made of some families and genera which have woods 

 of similar character and structure, but it is also necessary to point out 

 that there is no regular rule for determining orders and genera by means 

 of the wood, for in some cases the structure of the different component 

 genera or species presents characters of a very dissimilar type. In the 

 genus Dalbergia, for instance, there is a very great dissimilarity, so that 

 while three species (see p. 12-1<) have hard dark-coloured heavy woods, 

 others have white, often soft, woods without heartwood, and one species 

 has the peculiarity of a wood divided into concentric rings, which are often 

 separable, of alternate layers of wood and bark-like tissue. 



But, in general, it may be said that in the same genus the wood 

 structure is usually constant, and in this way the character may often 

 serve as a valuable aid in botanic investigation, as it has constantly done 

 in palaeontology. 



It is not always easy to give in words an explanation of the reasons 

 which lead one who is tolerably conversant with the structure of woods to 

 pronounce an opinion ; there arc often characters of appearance, touch, 

 colour, odour, &c., which afford clues, as well as the arrangement and 

 relative size of the pores and medullary rays, and the presence or absemv 

 of annual rings; so that it is really only experience and habit that can 

 teach us to recognize, from a mere inspection of a wood, the place which 

 it ought to occupy in the natural system. 



As an instance of how the btruclure oi' a wood may bear out an opinion 



