This section is from "The Horticulturist, And Journal Of Rural Art And Rural Taste", by P. Barry, A. J. Downing, J. Jay Smith, Peter B. Mead, F. W. Woodward, Henry T. Williams. Also available from Amazon: Horticulturist and Journal of Rural Art and Rural Taste.
As much as twenty years ago, Mohl suggested that the coiling of tendrils "resulted from an irritability excited by contact." In 1850 he remarked that this view has had no particular approval to boast of, yet that nothing better has been put in its place. ' And in another paragraph of his admirable little treatise on the vegetable cell (contributed to Wagner's "Cyclopaedia of Physiology)," he briefly says: "In my opinion, a dull irritability exists in the stems of twining plants and in tendrils." In other words, he suggests that the phenomenon is of the same nature, and owns the same cause (whatever that may be) as the closing of the leaves of the Sensitive plant at the touch, and a variety of similar movements observed in plants. The object of this note is to remark that the correctness of this view may be readily demonstrated.
For the tendrils in several common plants will coil up .more or less promptly after being touched, or brought with a slight force into contact with a foreign body, and in some plants the movement of coiling is rapid enough to be directly seen by the eye: indeed, is considerably quicker than is needful for being visible. And, to complete the parallel, as the leaves of the Sensitive plant, and the like, after closing by irritation, resume after a while their ordinary expanded position, so the tendrils in two species of the Cucurbitaceae, or squash family, experimented upon, after coiling in consequence of a touch, will uncoil into a straight position in the course of an hour; then they will coil up at a second touch, often more quickly than before; and this may be repeated three or four times in the course of six or seven hours.
My cursory observations have been principally made upon the Bur-Cucumber (Sicyos angu-latus). To Bee the movement well, full-grown and out-stretched tendrils, which have not reached any support, should be selected, and a warm day; 77° Fahr. is high enough.
A tendril which was straight, except a slight hook at the tip, on being gently touched once or twice with a piece of wood on the upper side, coiled at the end into 2 1/2 - 3 turns within a minute and a half. The motion began after an interval of several seconds, and fully half the coiling was quick enough to be very distinctly seen. After a little more than an hour had elapsed, it was found to be straight again. The contact was repeated, timing the result by the second-hand of a watch. The coiling began with four seconds, and made one circle and a quarter in about four seconds.
It had straightened again in an hour and live minutes (perhaps sooner, but it was then observed); and it coiled the third time on being touched rather firmly, but not so quickly as before, viz., 1 1/4 turns in half a minute.
I have reason to think that the movement is caused by a contraction of the cells on the concave side of the coil, but I have not had an opportunity for making a decisive experiment. - Prof. Asa Gray, in the Proceedings of the American Academy of Arts and Sciences.
The Illustrated Bouquet, published by Messrs. Henderson, of the Wellington Road, London, improves with time. Part V. contains some very remarkable things extremely well figured. First and foremost is a capital figure of the Bootan Rhododendron, called R. Nuttal-lii, certainly one of the most glorious plants in cultivation, not yielding precedence to even R. Dalhousianum itself. With noble leaves of the largest size it bears masses of golden-eyed snow white flowers, represented in the drawings of eighteen inches round the edge, and actually in a dried specimen before us, measuring something more; a real goddess this among the crowds of inferior deities that follow in the train of Flora. Unfortunately the species is strictly greenhouse, not being able to bear even an inconsiderable degree of frost. It is proba-bly the same as the Rhododendron found by Griffith in Bootan, on the ascent to Chupcha, growing in a wood of Quercus ilicifolia, at an elevation of 8,000 to 8,500 feet, and described as a small tree.
The second plate is occupied by a very good figure of Tritoma Uvaria, that gorgeous autumn hardy plant which has recovered its long lost reputation in consequence of having been taken into the favor of royalty at Osborne. The author of the remarks accompanying the plate makes five species of Tritoma, and three varieties of T. Uvaria itself.
A third plate is filled with huge flowers of four new Indian Azaleas, from the pencil of a Belgian artist; viz., Leopold I. and Due de Brabant, rose-colored and much alike; Etoile de Gand, pink, with a few spots of carmine; and Reine des Panachees, white, streaked with crimson, apparently rather coarse and too much like other stripes now in cultivation.
The last plate includes a variety of Gardenia radicans, and a very fine representation of Messrs. Lee's beautiful Torenia now called pulcherrima, without exaggeration.