Jan. 1899.] BOTANICAL SOCIETY OF EDINBURGH 165 



been badly damaged by insects. In these quiescent l)uds, 

 the primary leaves having been only partially changed to 

 scales, the so-called rosette shoot results. On the other 

 hand, according to Hempel and Wilhelm, the cryptoblasts 

 of Pinus Laricio often develop after a year or two into 

 normal branches of unlimited growth, which are covered 

 with scale leaves, in whose axils foliar spurs are produced, 

 and this happens with apparently no cause. 



My observations go to confirm the statements of these 

 latter investigators, that the dormant buds can produce 

 more than mere rosette shoots. I have frequently found 

 between the old branches of a whorl young shoots only a 

 few millimetres in length, on which bifoliar spurs were 

 appearing. On a young Scots pine I found a ring of 

 some very young shoots developing between the branches 

 of a whorl which was four years old. That these young 

 shoots were not developed from interfoliar buds was 

 evident for two reasons — first, they showed no subtending 

 leaf-scars ; second, the main axis had lost all its bifoliar 

 spurs for a considerable distance above this whorl. At 

 present I have numerous experiments in course of progress, 

 by which I hope to obtain evidence confirmatory of the 

 opinion I have just expressed as to the origin of these 

 extra shoots. 



Hartig states that the conditions under which such 

 buds develop are very various ; but they have this in 

 common, that an increased supply of nutriment reaches 

 the buds, and this may be caused, for example, by pruning, 

 light thinning, defoliation by insects, or late frosts. All 

 these factors are at work in the plantation where I made 

 my observations. It is true, the late frosts were not very 

 intense, and the defoliation was only partial, but to 

 compensate, the thinning and pruning were very severe. 



Very similar to the dormant are the interfoliar buds 

 which occur between the needles at the apex of the branch 

 of limited growth. The first leaves of the branch of 

 limited growth form the needle sheath, the last leaves the 

 needles themselves, Ijetween which is found the interfoliar 

 bud, which generally undergoes no further development. 



The duration of the bifoliar spur varies from one and a 

 half to twenty years, according to the age of the tree and 



