254 Canadian Record of Science. 



between the stem and leaf where the tendrils are absent, a 

 strong, well-developed branchlet being the rare exception 

 where the tendril is present. These branchlets are, of 

 course, at the base of the petiole and not on the side of the 

 stem where the tendril would be expected, were all the 

 points of junction tendril-bearing. Dr. Balfour's contention 

 is that in the vine and in Ampelopsis Veitchii, the tendrils are 

 to be looked upon as the terminations of separate axes or as 

 transformed terminal buds, and he adds that in the vine 

 there are no young buds seen in the angle between the 

 stem and leaves nor between the stem and tendrils. In 

 Ampelopsis quinquefolia there are, however, invariably young 

 buds in the angles between the leaves and stem wherever 

 the opposite side of the stem is not tendril-bearing, and 

 also in the similar angle of the leaf next below, but not 

 in the angle of the leaf succeeding that lower on the 

 stem. In other words, at the base of every third 

 petiole — but only where a tendril occurs on the opposite 

 side from the petiole — a young bud or branchlet is wanting. • 

 In Vitis cordifolia, again, there is always a bad, and, in 

 some cases, two, in the angle of each leaf with the stem. 

 As mentioned already, these young buds sometimes develop 

 into vigorous, healthy branches. There is, therefore, in 

 these two species not sufficient foundation for the theory 

 that the tendrils are terminations of separate axes or modi- 

 fications of the axes, nor do external appearances in these 

 plants suggest it, though it might possibly apply in the 

 case of the lower tendril of each set of two tendrils in the 

 case of Ampelopsis. Br. Asa Gray's view of the tendrils of 

 these two plants is that they are branches of a very slender 

 kind, similar to runners, but intended for climbing and not 

 for propagation, and therefore destitute of buds or leaves. 

 Two instances I have met with of the Virginian Creeper, 

 gave colour to this view, in that each of the two tendrils 

 bore a solitary trifoliate leaf. 



There appear, however, to me, rather to be affinities be- 

 tween the tendrils of Ampelopsis qwnquefolia and the peduncle 

 and pedicels of its flower. 1 The angulation is somewhat simi- 

 1 Darwin. Climbing Plants, 136. 



