168 



ORGANOGRAPHY, 



simple leaves, and similar terms are accordingly used in describ- 

 ing them. We have now therefore only to speak of compound 

 leaves as a whole, and tlie terms Avhich are used in describing 

 their various modifications. We divide them into two heads, 

 namely, 1. Pinnately or feather veined Compound leaves, and 2. 

 Palmateiy or radiated veined Compound leavis. 



1. Pinnatehj-veinid Compound leaves. — When a leaf present- 

 ing this kind of venation is separated into distinct portions or 

 leaflets, it is termed pinnate {Jig. 334). The leaflets (or pinnce 

 as they are then called) are arranged along the sides of the 

 rachis or common petiole in pairs, and according to their 

 number, the leaf is said to be vnijuyate or one-paired, as in 

 Lathi/rus sylvestris and latifolius, hijugate or two-paired, trijugate 

 or three-paired, and nuiltijugate or many-paired {Jig. 334). 

 Several kinds of pinnate leaves luive been distinguished. Thus 



Fig. 335. 



Fig 334. 



Fig. 336. 



Fig. 337. 



Fig. 334. Impari-pinnate or unequaUy pinnate leaf of Robinia. l-'ifl- 



33r>. Equally or nbruplly ph.nate leaf. Fvj. -W,. InUrriiple.l y 



pinnote k-af of the Potato {Sohinum tuberosum) /■'(/• JW/ . Jvyrotely 



pinnate leaf. 



when a ])innate leaf ends in a single leaflet {fg. 334), as in 

 Roses and the IClder, it is impari-pinnate or umynalli/ pinnate, or 

 pinnate with an odd leaflet ; it is ecjualli/ or abrupth/ pinnate, or 

 J)ari■pinnat€,^\h^in it ends in a pair of leaflets or pinnaj (^^r. 335), 



