12.] CHAPTER I[. SPECIAL MORPHOLOGY OF THE MEMBERS. 



53 



such a leaf is said to be ternate. This segmentation may be repeated in the 

 leaflets, when the leaf is said to be biternate, triternate, etc. On comparing 

 Fig. 32 B and F, the close relation between pinnate and palmate leaves be- 

 comes apparent. A ternate leaf is usually considered to belong to the palmate 

 type, but it might almost equally well be regarded as an imparipinnate uniju- 

 gate leaf. 



I' 1 



FIG. 32. Segmentation of leaves, p Petiole ; p' petiolule ; /' leaflet ; r phyllopodium. A 

 Palmatifid or palmately lobed leaf of Geranium. B Ternate (compound palmate) leaf of 

 Clover. C Pinnatisected leaf of Shepherd's Purse (Capsella). Compound pinnate leaves : 

 D Imparipinnate leaf of Hippocrepis comosa; t terminal leaflet. E Paripinnate leaf of 

 Pistacia Lentiscus ; a wing of the phyllopodium. F Imparipinnate unijugate leaf of Medi- 

 cago. This differs from B, which is ternate, inasmuch as the secondary leaf-stalks p' do 

 not all spring from one point, but the common leaf-stalk p extends beyond the insertion 

 of the single pair of pinnae ; s projecting rib, or mucro. G Leaf of the Orange ; the articu- 

 lation a between the blade and the winged petiole shows that it is really a compound leaf 

 with a single terminal leaflet. H Bipinnate leaf of Acacia : v' secondary axis ; /" secondary 

 pinnse or pinnules. 



