470 RUTACE/E. [Hvpogyxous Exogexs. 



St. Hilaire. Rutese are allied to Bean-capers through Peganuin, which A. de Jussieu 

 actually stations among the former, although its stipulate leaves, destitute of pellucid 

 dots, seem to determine its greatest affinity to be with the latter. Rueworts differ 

 from Citronworts in their capsular fruit invariably splitting into its component parts, 

 from Xanthoxyls in the flowers being , and from Anacards (Anacardiacese) in the 

 ovules being sessile and suspended, not attached to the end of a long cord rising from 

 the base of the ovary. The Cneorese of Mr. Barker Webb seem to be a form of this 

 Order of Rueworts rather than of Xanthoxyls ; for their flowers are and their habit 

 is not unlike that of Phebalium. The truly monopetalous corolla of Correa is very 

 remarkable, and brings this Order so close to Heathworts that the indefinite seeds, po- 

 rous anthers, but more especially the abundant albumen of the latter, form the principal 

 marks of distinction. 



M. Adrien de Jussieu thus describes the peculiarities of the pistil in that division of 

 the Order which is called Diosniere : — " The ovaries, whether combined by their central 

 axis, or distinct, always contain 2 ovules ; if 4, or sometimes but 1 , are found, that occurs 

 only in genera stationed at the extreme limits of the group. They are collateral, or 

 more frequently placed one above the other, and then one is usually ascending, and the 

 other suspended. This position, which at first sight appears singular, is very natural ; 

 for the ovary is usually pierced by the vessels of the style only in the middle, and it is 

 at that point that the two ovules are inserted, both at nearly the same height. If, 

 therefore, they are placed one above the other, it is indispensable that one should 

 ascend and the other descend. These ovules may be considered peritropal, rather than 

 either ascending or suspended, or in other terms, attached by their middle rather than 

 by either extremity." — " If the ovary of a Diosmea is divided across, its coat will be 

 found to consist of two layers, the outer rather the most fleshy, and the inner thin or 

 almost absent on the side next the axis, the side which is traversed from bottom to top 

 by the vessels of the peduncle. These vessels at a certain height, meet those of the 

 style, either at the point of its insertion or. below it ; united to these, they penetrate the 

 cavity of the cell, the shell of which they pierce, and there form funiculi, to which the 

 ovules are attached. Thus far the structure of Diosmea is little different from that of 

 other Rutaceous plants. But this becomes modified as the ovary advances towards the 

 state of fruit. The endocarp hardens by degrees, and at the same time separates from 

 the sarcocarp. Its form resembles that of a bivalve shell, and may be more especially 

 compared to that of a muscle ; it presents two extremities, one superior, the other 

 inferior, two lateral faces which are more or less convex, and two edges more or less 

 acute, which unite them, the one external, the other internal. The two valves are 

 woody and touch at the edges, except perhaps at a part of their inside where they are 

 separated ; this space is filled by a membrane which passes from one to the other : it is 

 either slightly fleshy, or, which is more common, extremely thin, thickened in the mid- 

 dle by the passage of the vessels of the seed which penetrate it ; and as, after having 

 pierced it, they are almost immediately inserted into the seed, the latter appears to be 

 actually borne by the membrane itself. When the fruit is perfectly ripe, the sarcocarp 

 of each cell opens from above inwards, following a longitudinal furrow, which had 

 become visible some time previously. Its inner surface is seen to be covered by pro- 

 jecting lignified vessels, which are directed obliquely from the inner edge towards the 

 outer, and are indicated externally by some transverse projections. The endocarp is 

 loose in the inside of the shell, unless at its membrane, by means of which it continues 

 to preserve some degree of adhesion with the other parts ; but it soon opens, the two 

 valves separate in different directions, and force out the seeds. When tins separation 

 takes place, the membrane is torn all round, and either falls away or sticks to the seed. 

 In the latter case it is found attached to the hilum, if one seed only has ripened ; but 

 then in removing it, the remains of the abortive ovule may be found on one side. If 

 both seeds have arrived at maturity, they are usually seen one resting on the other by 

 their contiguous flattened extremities, and the membrane extends along their inner 

 edge, being enlarged at their point of contact, where two transverse prolongations are 

 perceptible." 



Ruteae are found in the south of Europe, whence they extend in our hemisphere as 

 far as the limits of the Old World, following the southern part of the temperate zone, 

 and very rarely advancing within the tropics. Dictamnus is found in the south of 

 Europe. The Cape of Good Hope is covered with different species of Diosma and 

 nearly allied genera ; New Holland abounds in Boronias, Phebaliums, Correas, Erios- 

 temons, and the like ; great numbers of Cuspariere and Pilocarpese inhabit the 

 equinoctial regions of America. 



The species are characterised by their powerful odour and their bitterness ; they act 

 principally on the nerves. Common Rue, and another species, are said to be emmena- 

 gogue, anthelmintic, and sudorific. Ruta montana, a Spanish plant, is so acrid that it 



