I50 



SCIENCE-GOSSIP. 



CHARACTERISTIC BRANCHING OF BRITISH FOREST-TREES. 



By the Rev. W. H. Purchas. 



(Continued Jrom page 95.) 



The Horse-Chestnut. 

 A LTHOUGH the horse-chestnut {JE$cxdus hippo- 

 •^ castanum, L.) is not a native of Britain, 

 having apparently been introduced from Asia, this 

 noble tree has so long been known and is so often 

 planted for the sake of ornament that it may well 

 claim a place with others in these notes. 



Position of leaves. — The large leaves, divided to 

 the base into seven lobes and borne on peduncles 

 which are often nine inches or more in length, are 

 ranged in opposite pairs as in the ash. Hence the 

 branches which arise from their axillary buds are 

 in opposite pairs also, at least when all the axillary 



internodes, varying 

 length. The larger 



from one to several inches in 

 of the yearly shoots close up at 

 the end of summer into a win- 

 ter bud, which contains the 

 inflorescence ready to burst 

 forth in the following spring. 

 This terminal bud is often 

 accompanied by a pair of 

 leaf-buds formed in the axils 

 of the last pair of leaves. 

 These leaf -buds give rise 

 in the next season to leafy 

 shoots which do not, until 







Horse-Chestnut {Aisailus hippocastantnn). 



buds are developed, for it frequently happens, as it 

 does also in the ash, that one of a pair of buds 

 remains dormant and gradually perishes. 



Position of flowers. ^ — The inflorescence is terminal , 

 as in the sycamore, but on a much more lengthened 

 leafy shoot. In the sycamore one or at most two 

 short joints separate the group of flowers from the 

 end of the last year's wood, while in the horse- 

 chestnut a shoot of at least three joints intervenes. 

 Some of these joints are as much as three or four 

 inches long ; thus the whole yearly growth, includ- 

 ing the panicle or thyrse of flowers, will sometimes 

 reach a length of eighteen or twenty inches. 



Length of joints or internodes.— The yearly shoot 

 seems to be completed more rapidly than in most 

 trees. It consists of few (three or more) but long 



a future year, acquire the robustness which 

 seems to be needful for forming an inflores- 

 cence in their terminal bud. I may remark 

 that when the winter buds swell and open and 

 throw off their scales the internodes between these 

 latter do not lengthen as do those between the 

 young leaves ; thus their position is indicated by 

 a little band of scars, and such bands of scars 

 point out the starting-point of each season's 

 growth. 



Angle made with the main stem or branch.— 

 The angle at which the lesser branches leave 

 their parent branch is less than half a right-angle ; 

 thus the pair of branchlets which are developed 

 from the buds formed in the axils of the pair of 

 leaves nearest to the inflorescence do not start off 



