RUTACE^E 317 



RUTACE^E, 



Benth. et Hook. Gen. PI. i. 278. 



Fruit and Seed. The carpels forming the ovary in this 

 Order vary from three to five, rarely more or less as in Tham- 

 nosma and Atalantia, some species of which have dimerous 

 ovaries. Whatever the number of carpels, they are united into 

 an ovary with as many cells, except in Galipea, Zanthoxylum, 

 and a few others, where the carpels are quite free. The ovules 

 in each cell are very frequently two and superposed, but they 

 also vary from three or four to many. They are pendulous, 

 anatropous, or semianatropous. The raphe is ventral, the mi- 

 cropyle superior. The fruit varies greatly, but is capsular in 

 the more typical Eutaceas, opening by valves along the back or 

 at the top as in Euta, or breaking up into cocci which dehisce 

 along the ventral suture. In many cases the exocarp breaks 

 away elastically from a coriaceous, horny, crustaceous, or car- 

 tilaginous endocarp. In the tribe Toddaliese the fruit is often 

 baccate or drupaceous ; instances of the latter are to be seen 

 in Skimmia, Toddalia, and Phellodendron. The fruit of Ptelea, 

 belonging to this tribe, is an orbicular samara, and in Helietta 

 it consists of three samaras. That of the tribe Aurantieae is 

 most often pulpy with a coriaceous separable rind. 



The seeds are oblong as in Ptelea trifoliata, or often reni. 

 form as in Monnieria, Euta, and Boenninghausenia, or obovoid 

 as in Dictamnus, Skimmia, Citrus, and others. They are 

 usually suspended from the top or the middle of the pla- 

 centas. The testa is spongy, or more often crustaceous and 

 shining as in Dictamnus, or it is pitted and granular. The 

 outer coat is said to resemble an aril in Hortia. Endosperm 

 is scanty or wanting in a large number of genera ; but in the 

 tribes Euteae, Boronieae, Toddalieaa, and in most of the Zan- 

 thoxyleae it is present in some quantity and fleshy, sometimes 

 also oily. The embryo is very frequently curved according to 

 the shape of the seed, or straight where the latter is obovoid. 

 The radicle is superior and varies in length, being as long as 



