286 On some Brazilian Climbing-Plants. 



of two parts, separated by a small swelling - - the inferior being straight, the 

 superior curved, with its end rolled into a helix. But what appears to be the 

 inferior part of a tendril is in fact the first internode of a young branch, the 

 swelling being its terminal bud, and the tendril really springs from this young 

 branch, from the angle of its first squamiform leaf, but nevertheless accompanied 

 by two stipules. The end of the tendril very soon rolls up into a helix; but it 

 does not lose by this the faculty of catching a support; on the contrary I know 

 of no other tendrils which become entangled with small objects so easily as these 

 rolled-up, highly elastic tendrils of the Caulotretiis. 



By far more interesting than the tendrils of Strychnos and Caulotretus are 

 those (PI. XXVII. figs, i and 2) of a climbing Papilionaceous plant with a woody 

 stem, which from its general aspect I suppose to belong to the Dalbergiece, Benth. 

 They consist of thin, slender, flexible, leafless branches, with numerous (12 25) 

 internodes, armed with sharp, hard, hook-like stipules. The young, soft, herbaceous 

 shoots of this plant which rise from the ground are leafless. I saw one, seven 

 feet high, which in its lower half was naked, while the upper half bore about a 

 dozen tendrils stretched out in every direction. The oldest of these tendrils were 

 from nine to twelve inches long, and armed with from twelve to sixteen pairs of 

 sharp hooks: at the sides of the younger tendrils there were large, foliaceous, 

 deciduous stipules, and at their bases very small bract-like leaves. The hooks of 

 the tendrils are evidently stipules, which so often in this family assume the form 

 of hooks or spines; in fact, while in the older tendrils they are strongly curved, 

 and have a hard, sharp, darkly coloured apex, at the summits of the younger 

 ones they are straight, soft, and green, resembling in this early state the much 

 larger stipules at the bases of the tendrils. Afterwards, on the summit of the 

 shoot, true leaves are developed at the bases of the tendrils instead of the small 

 rudimentary ones; and finally, when the plant has reached the light, and spreads 

 over the upper surface of a thicket or tree, the tendrils disappear. The inverse 

 may be observed when the plant sets out on the conquest of a new dominion, a 

 neighbouring tree for instance. Then a branch bearing only leaves begins to 

 produce on its tip tendrils supported by leaves, and finally, growing rapidly to a 

 long slender shoot, it produces only tendrils, the leaves being replaced by small 

 squamae. Thus in this plant, the branches assume four different shapes: -- ist, 

 tendrils, leafless, armed with hook -like stipules; 2nd, long, slender, leafless shoots, 

 bearing tendrils and broad deciduous stipules; 3rd, branches with leaves, from 

 the axils of which tendrils spring; and 4th, branches bearing only leaves without 

 tendrils. Between the leaf and the tendril there is an accessory bud (fig. i 6), 

 which often developes into a branch; these branches issuing from the accessory 

 buds seem never to produce tendrils. The tendrils, after having clasped a support, 

 thicken partially where they are in contact with it (fig. i a). Tendrils which have 

 caught nothing behave in different ways. Some wither and fall after contracting 

 irregularly. Others likewise become flexuous, or contract into a spire, or occasio- 

 nally into a helix, but remain, thickening somewhat and becoming ligneous and 

 rigid. Others produce branches from one or some of their internodes: this also 

 occurs, and perhaps more frequently, with tendrils which have found a support; 

 in this case the tendrils thicken much, and sometimes attain a diameter of more 



