Pyrus 



143 



6. Pyrus Sorbus, Gaertner. Central and Southern Europe. Winter buds 



greenish, viscid, pubescent only at the tip ; under surface of the 

 leaves slightly pubescent in spring, soon becoming glabrous. 



II. Leaves pinnate, but upper 3 <?r 5 leaflets coalesced or decurrent by their bases on 



the rhachis} 



7. Pyrus Aucuparia, Gaertner, var, satureifolia, Koch. A hybrid. Differs 



from the common form in the coalescence into one large segment of 

 the 3 upper leaflets ; leaflets glabrous beneath. 



8. Pyrus Aucuparia, Gaertner, var. decurrens, Koehne {Pyrus lanuginosa, 



Hort. non DC.) A hybrid. Upper leaflets decurrent on the rhachis 

 by broad bases, often the upper 3 or 5 coalescing into one segment ; 

 leaflets tomentose beneath. 



III. Leaflets pinnate or deeply cut at the base, with 1-4 pairs of segments, the upper 

 part of the leaf lobed or serrate ; leaves very variable in shape} 



9. Pyrus hybrida, Moench. A shrub of hybrid origin. Main axis of the 



leaf glandular above, under surface of the leaf sparingly pubescent, the 

 parents being Pyrus aucuparia and Pyrus arbutifolia. 



10. Pyrus pinnatiflda, Ehrhart. A hybrid. Axis of the leaf without glands, 

 under surface densely grey tomentose. 



IV. Leaves simple, lobed. 



A. Under surface of the leaf glabrous, or nearly so, light green in colour. 



11. Pyrus torminalis, Ehrhart. Europe, Algeria, Asia Minor, and the 



Caucasus. 



B. Under surf ace of the leaf grey tomentose. 



12. Pyrus crataegifolia, Savi. Italy. Leaves small, resembling those of a 



hawthorn, on each side 4-6 triangular-ovate toothed lobes. 



1 3. Pyrus latifolia, Boswell Syme. Britain, France, Spain, Central Europe. 



Leaves broad-oval with a wide base ; lobes decreasing from below 

 upwards, small triangular, separated by sinuses, which form a right 

 angle and are not narrowed. In some forms the lobes are mucronate, 

 in others cuspidate ; and, in var. decipiens, the outline of the leaf is like 

 intermedia, but the lobing is different. 



14. Pyrus intermedia, Ehrhart. Europe. Leaves elliptic, with a usually 



narrow base, lobes decreasing from below upwards, rounded, mucronate, 

 separated by narrow sinuses, which are very acute or almost closed at 

 their bases. This includes several forms : 



Mougeoti. Leaves with 9-12 pairs of nerves, lobes shallow. 



' These two sections comprise hybrids, the leaves of which vary in shape, not only on different individual trees, but often 

 also on a branch. Hybrid origin may always be suspected when such variation is observed, o.- when the lobing or cutting is 

 irregular and not symmetrical. 



