70 



SCIENCE-GOSSIP. 



CHARACTERISTIC BRANCHING OF BRITISH FOREST-TREES. 



By the Rev. W. H. Purchas. 



{Continued from page 43.) 



The Lime. 



npHERE are in Britain three different forms of 

 lime-trees ; whether distinct as species, or 

 ■whether modifications of one single species, is a 

 question which is not here discussed. They have 

 varying claims to be considered indigenous, and 

 the names bv which thev have been usuallv known 



trees are found in the size and clothing of the 

 leaves and the proportionate length of their stalks, 

 and also in the shape, size and texture of the fruit. 

 The arrangement of the leaves on the stem and the 

 position of the flov.-ers are alike in all, and it is %^-ith 

 these that vre are chiefly here concerned. 



Small-leaved Li.me. Tilia parvifolia, early srunmer staie. 



to British botanists are (i) Tilia parvifolia, Ehrh., 

 the small-leaved lime, the most truly wild form, 

 as it is pretty certainly a native in various 

 woods in the southern and south-western coimties ; 

 (2) the common lime Tilia intermedia, D.C., which 

 exists chiefly, if not altogether, as a planted tree ; 

 and (3) Tilia grandifolia,oi 'Ehrh.., the large-leaved 

 lime, which, although often planted, is met with in 

 some localities, such as the rocky limestone woods 

 of the Wye Valley (Gloucestershire and Hereford- 

 shire), where it is difficult to believe that it can 

 be other than a native. 



The botanical differences between these three 



The arrangement of the leaves in the lime is the 

 same as in the elm and in the beech, i.e. two- 

 ranked, each third leaf standing immediately over 

 the first, and hence giving rise to a two-ranked 

 order in the secondary branches. 



The flowers, which are borne in small stalked 

 pendulous clusters (cymes), spring not as in the 

 elm, immediately from axillary buds on the 

 pre\-ious year's wood, but from leafy shoots of the 

 current year arising from those axillary buds ; 

 they thus belong to a younger order of growths 

 than in the case of the elm. The axil of every leaf, 

 or nearly e%-ery leaf save the lower ones, on these 



