2i6 FREAKS OF PLANT LIFE. 



above figures in illustration arc from a cultivated pas- 

 sion-flower {Passiflora cdii/is). 



There remain only the two sections, of scramblers, 

 or plants which ascend merely by hooks, and root 

 climbers, which ascend by means of rootlets, to be 

 described. As these do not exhibit many remarkable 

 phenomena a few observations will suffice. The 

 scramblers are represented by that very common 

 Aveed the " cleavers " or " goosegrass " {Galuiui 

 aparine)^ which scrambles up hedges and amongst 

 thickets by means of the recurved hooks with which 

 the stems are liberally provided. The young shoots 

 appear to possess no spontaneous rotation, and the 

 climbing habit is literally reduced to a scrambling, 

 the lowest and most imperfect climbing with which 

 we are acquainted. Some kinds of roses would alsc> 

 find a place in this section, for they will scramble 

 up the walls of a house if there is a trellis-work to 

 assist them. Professor Asa Gray,^ explaining this 

 phenomenon, in reference especially to the Michigan 

 rose {Rosa setigcra), remarks that the summer shoots 

 are strongly disposed to push into dark crevices and 

 away from the light, so that in pursuance of this habit 

 they would be sure to thrust themselves under a 

 trellis, whilst the lateral shoots, developed in the fol- 

 lowing spring, will emerge from the trellis in search 

 of the light. This alternate mode of growing 



" American Journal of Science," vol. xl., p. 282. 



