TENDRIL-BEAftEKS. 59 



On one occasion, when a tendril had curled round a small stick, 

 half an inch in diameter, an adhesive disk was formed ; but gene- 

 rally the tendrils can do nothing with smooth sticks or posts. If, 

 however, the tip of any one branch can curl round the minutest 

 projecting point, the other branches will form disks, especially if 

 they can find crevices to crawl into. The tendril quite fails to 

 attach itself to a brick wall. 



I infer that the disks or balls secrete some resinous adhesive 

 matter, from the adherence of the fibres to them, but more espe- 

 cially from such fibres becoming loose after immersion in sul- 

 phuric ether, which likewise removes small, brown, glistening points 

 that can generally be seen on the surface of the older disks. If 

 the hooked extremities of the tendrils touch nothing, the cellular 

 outgrowth, as far as I have seen, never commences ; but tem- 

 porary contact during a moderate time causes small disks to be 

 formed. I have seen eight disks developed on one tendril. After 

 the development of the disks, the tendrils, which now become 

 spirally contracted, likewise become woody and very strong. A 

 tendril in this state supported nearly seven ounces, and would 

 apparently have supported a considerably greater weight had not 

 the fibres of flax to which the disks were attached yielded. 



From the facts above given, I infer that though the tendrils 

 of this Bignonia can occasionally adhere to smooth cylindrical 

 sticks and often to rugged bark, yet that they are specially adapted 

 to climb trees clothed with lichens, mosses, or with Polypodium 

 incanum, which I hear from Professor Asa Gray is the case with 

 the forest-trees where this Bignonia grows. Finally, it is a highly 

 remarkable fact that a leaf should become metamorphosed into a 

 branched organ which turns from the light, and which can by its 

 extremities either crawl like roots into crevices, or seize hold of 

 minute projecting points, these extremities subsequently form- 

 ing cellular masses which envelope by their growth the finest fibres 

 and secrete an adhesive cement. 



Eccrcmocarpus scaler {Bignoniaceai). — Plants in the green- 

 house, though growing pretty well, showed no spontaneous move- 

 ments in their shoots or tendrils ; but, removed to the hot-house, 

 the young internodes revolved at rates varying from 3 h. 15 m. to 

 Ih. 13m.: at this latter unusually quick rate one large circle 

 was swept; but generally the circles or ellipses were small, and 

 sometimes the course pursued was extremely irregular. An inter- 

 node which had made several revolutions would sometimes stand 



