ORDER OLEACE^E, OH OLIVE TRIBE. ASH. 473 



most common of the British species is the Privet, the fructification 

 of which may be taken as an illustration of that of the order. 

 The calyx is a four-toothed cup ; and the corolla is formed ot 

 the same number of petals, adherent at their lower part into a 

 tube, within which are two stamens. The existence of only two 

 stamens within a regular monopetalous corolla, is a character 

 which is nearly peculiar to this order, being shared with it only 

 i)y the Jasmine tribe. The ovary contains two cells ; and from 

 the top of 'each hang down two ovules. The style is single, and 

 is terminated by a two-lobed stigma. The ovary changes in 

 ripening into a small round succulent fruit or berry, containing 

 but one seed, the others not having been developed. These 

 are the general characters of the Olive tribe ; but there are some 

 remarkable exceptions. The Ash, for example, is placed in this 

 tribe, although it is destitute of corolla ; for although this cha- 

 racter would, if taken alone, cause a place to be assigned to it 

 in the next sub-class, rather than in this, yet when it is remem- 

 bered that the natural system is founded, not upon one or two 

 characters only, but upon general conformity, it will be seen 

 that the proper place of the Ash is in this order, since it agrees 

 with the Olive in every important particular, except the absence 

 of the corolla. A curious circumstance, which unequivocally 

 proves their near relationship, is that the Ash and the Olive will 

 graft very well together. 



648. The most important species of this order is undoubtedly 

 the Olive, the extensive cultivation of which in warm countries, 

 on account of the oil yielded by its fruit, has been already 

 noticed. The wood of the Olive is beautifully veined and takes 

 a high polish ; and having also an agreeable smell, it is much 

 esteemed for ornamental work. The Ash is one of the most 

 valuable of trees ; both on account of the number of useful pur- 

 poses to which its wood is applied ; and because it flourishes in 

 a greater variety of soil and situation, than any other tree pro- 

 ducing equally good timber. It differs too, from most other 

 trees in this, that its value is increased, rather than diminished, 

 by the rapidity of its growth. The wood of the Ash is chiefly 

 distinguished by its elasticity ; so that, although much less tough 



