Chap. V. HOOK-CLIMBEKS. 183 



CHAPTEE V. 



Hook asl Root-Climbebs. — Coxcluuing Eemabks. 



PLnta climbing by the aid of hooks, or merely scrambling over other 

 plants — Eoot-climbers, adhesive matter secreted by the rootlets — 

 General conclusions with respect to climbing plants, and the stages 

 of their development. 



Eooh-Glimbers. — In my introductory remarks, I stated 

 tiat, besides the two first great classes of climbing 

 plants, namely, those which twine round a support, 

 and those endowed with irritability enabling them to 

 seize hold of objects by means of their petioles or 

 tendrils, there are two other classes, hook-climbers and 

 root-climbers. Many plants, moreover, as Fritz Miiller 

 has remarked,* climb or scramble up thickets in a still 

 more simple fashion, without any special aid, excepting 

 that their leading shoots are generally long and flexible. 

 It may, however, be suspected from what follows, that 

 these shoots in some cases tend to avoid the light. 

 The few hook-climbers which I have observed, namely, 

 Galimn, aparine, Rubus australis, and some climbing 



* Journal of Linn. Soc. vol. ix. plants growing beneath other and 



p. 348. Professor G. Jaeger has well taller species or trees, are naturally 



remarked (' In Saehen Darwin's, those which would be developid 



insbesoudere contra Wigand,' into climbers ; and such plants, 



1874, p. 106) that it is highly from stretching towards the light, 



characteristic of climbing plants to and Irom not being mucli agitated 



produce thin, elongated, and flexi- by the wind, tend to produce long, 



ble stems. He further remarks that thin and flexible shoots. 



