172 BE VIEWS. 



would, many of them, pretty surely place themselves under 

 the trellis, and the lateral shoots of the next spring would 

 emerge as they seek the light. "VVe suspect this is also true 

 of the Sweet Brier. 



Twiners and Leaf-climbers having been considered, Ten- 

 dril-bearers, which are the highest style of climbing plants, 

 next demand our attention. But our analysis of this im- 

 portant part of Mr. Darwin's treatise must be dispropor- 

 tionably brief. 



There are two kinds of movement exhibited by plants, 

 wliich should be distinguished. 1st, Automatic, usually con- 

 tinued movements, not set in action by extraneous invitation. 

 The gyratory movement of the small leaflets of Des/nodium 

 gyrans is an exalted instance of this. 2d, Movements in con- 

 sequence of the contact or action of an extraneous body, — of 

 which those of the leaves of the Sensitive Plant may be taken 

 as the type. Twining stems, as has been seen, strikingly ex- 

 hibit the first, and their coiling around a support is a conse- 

 quence of it. 



Tendrils for the most part execute both kinds of move- 

 ment. They revolve, with some exceptions, like twining 

 stems ; and they are all more or less sensitive to contact, — 

 usually more so than the petioles of leaf -climbers, — bending 

 toward the impinging body so as to hook or clasp around it, 

 if the size will allow.- Different tendrils act differently in 

 some respects, some revolving freely, and sweeping wide 

 circuits, some less evidently, and some, like those of the Vir- 

 ginia Creeper, do not revolve at all, but turn from the light 

 to the dark. But whether the tendril is the homologue of 

 a leaf, or of a stem (or of a peduncle, which is the same 

 thing), appears to make no difference in its action. On the 

 other hand their diversity of gifts in one and the same fam- 

 ily, or even in species of the same genus, is very remark- 

 able, as may be seen especially in tlie Bignonia Family, the 

 Grape Family, etc. So, also, the tendrils are commonly aided 

 in their endeavors by the revolving of the internodes of the 

 stem, but sometimes not, even in plants of tlie same genus 

 or family. Mr. Darwin takes up tendril-bearing plants by 



