101, 102.] 



THE COMPOUND LEAF. 



119 



and opposite. It is unequally pinnate (357) when the 

 rachis bears an odd terminal leaflet, and equally pin- 

 nate (356) when there is no terminal leaflet, and inter- 

 ruptedly pinnate when the leaflets are alternately large 

 and small (358). 



303. The number of leaflets in the pinnate leaf 

 varies from thirty pairs and upward (as in some Aca- 

 cias), down to three, when the leaf is said to be ter- 

 nate or trifoliate; or two, becoming ~binate ; or finally 



Compound leaves 354, Trifolium repens 



355, Desmodium rotundifolium. 

 358, Agrimonia. 



357, Cassia. 



even to one leaflet in the Lemon. Such a leaf is theo- 

 retically compound, on account of the leaflet (blade) 

 being articulated to the petiole. 



304. A Hpinnate leaf (twice pinnate) is formed 

 when the rachis bears pinnce or secondary pinnate 

 leaves, instead of leaflets (361), and tripinnate (thrice 

 pinnate) when pinnae take the places of the leaflets of 

 a bipinnate leaf (360). When the division is still more 

 complicated, the leaf is decompound. Different degrees 

 of division often exist in different parts of the same 



