70 Botany. 



423. P. cerasus, L. (DWARF CHERRY), 5, D. Shrub. Woods, 



hedges ; frequent ; the ancestor of the sweet varieties of 

 cultivated cherries. It keeps its leaves longer in S. Europe, 

 and in Ceylon is an evergreen. 



1. South side of Hayes Common, '06. W.H.G. 



2. Barnhurst, '06. R.H.C. 



424. P. padus, L. (BIRD CHERRY), 5. Planted. 



1. Lullingstone. H. 



a. Back of Shrewsbury House, Shooter's Hill (1836). 



NOTE. Cultivated sp, of Prunus include : 



1. P. armeniaca (Apricot), from Turkestan and Mongolia. 



2. P. amygdalus (Almond), from Turkestan and C. Asia. 



3. P. persica (Peach, Nectarine), prob. from N. China. 



4. P. laurocerasus (Cherry Laurel), an evergreen shrub from 



the Medit., commonly planted in gardens. Near the 

 base of the leaves on either side of the midrib are two 

 extra-floral nectaries, showing through as brownish 

 patches. It fls. freely away from the town. 



5. P. lusitanicus (Portuguese Laurel), with reddish shoots and 



petioles, grown in parks and gardens. 



(111) SPIRAEA, L. 



426. S. ulmaria, L. (MEADOW-SWEET), 6 8, P. Damp meadows, 



copses, and river-banks ; very common. Verv sweet- 

 scented, but no honey. 



427. S. niipendula, L. 57, P. Dry chalky pastures ; local. 



a. Nr. Kingsdown, Cole ; common on the chalk. Reeves. 



NOTE. The so-called Spiraea, commonly hawked round the 

 streets, is Astilbe japonica (Saxifragaceae). 



(112) RUBUS, L. (BRAMBLE), gen 58, all Shrubs exc. R, 



saxatilis and cham?emorus, which are herbs. A be- 

 wildering genus to systematists, and one still in a 

 state of transition. Of the various modifications 

 assumed by the Brambles some are no doubt con- 

 stant, but others are a question of environment. 

 B. and H regard the vast host of critical species 

 enumerated below (with the exception of R. idseus 

 and caesius), as all derivatives of one form, R. fruti- 

 cosus, L. Bab (9th Ed., 1904) gives 49 specific forms, 

 while the Rev. W. Movie Rogers, our authority on 

 the British Rubi, in his monograph, describes 112 

 critical species, besides numerous sub-species a,nd 

 varieties. But many of Roger's sp. are prob. hybrids ; 

 see " Observations on ' Set of British Rubi ' by Prof. 

 H. Sudre, Angers, 1904-" We have followed Rogers 

 (ex Bab.). 



