ENQUIRY INTO PLANTS, I. v. 4-vi. 2 



as that of the silver-fir, while others are rather break- 

 able/ such as the wood of the olive. Again some 

 are without knots/- as the stems of elder, others 

 have knots, as those of fir and silver-fir. 



Now such differences also must be ascribed to the 

 essential character of the plant : for the reason why 

 the wood of silver-fir is easily split is that the 

 grain is straight, while the reason why olive-wood is 

 easily broken ^ is that it is crooked and hard. Lime- 

 wood and some other Moods on the other hand are 

 easily bent because their sap is viscid.* Boxwood 

 and ebony are heavy because the grain is close, and 

 oak because it contains mineral matter.^ In like 

 manner the other peculiarities too can in some way 

 be referred to the essential character. 



Further 'special' diffennces. 



VI. Again there are differences in the ' core ' : in 

 the first place according as plants have any or have 

 none, as some say ^ is the case with elder among other 

 things ; and in the second place there are differences 

 between those which have it, since in different plants 

 it is res|>ectively fleshy, woody, or membranous ; 

 fleshy, as in vine fig apple pomegranate elder ferula ; 

 woody, as in Aleppo pine silver-fir fir ; in the last- 

 named " especially so, because it is resinous.- Harder 

 again and closer than these is the core of dog-wood 

 kermes-oak oak laburnum mulberry ebony nettle- 

 tree. 



The cores in themselves also differ in colour ; for 



that of ebony and oak is black, and in fact in 



the oak it is called • oak-black ' ; and in all these the 



core is harder and more brittle than the ordinary 



'' aurri conj. Sch.; avri} UAld.; avrrj MV ; ovt^j Po. 



39 



