THE STEM OF PLANTS. 27 
even resists efforts made to change it. Some, like the Bindweed 
(Fig. 22), if we suppose that they are twining round our own body, 
<n —— 
Fig. 27.—Procumbent Stem of Veronica officinalis. 
& LASLAAY EN. 
go from right to left ; Beka: as the Hop (Fig. 28), go from 
left to right. ‘The Lianas, which in the primitive forests pro- 
duce the most marked varied results,” says A. de Saint Hilaire, 
“and which impart to these cease their most picturesque 
beauties, are ligneous plants, some of them scandent, others volubile. 
These are the Bibouia Bauhinia, Cissus, &c., and though they all 
need a support, yet each plant has a bearing which is peculiar to 
itself. Some lianas resemble wavy ribbons; others are twisted, and 
describe large spirals. They hang in festoons, wind about among 
the trees, leap from one tree to another, and entangling themselves. 
together, forming masses of leaves and flowers, so that the observer 
finds it difficult to distinguish to which tree it belongs.” 
These Lianas of the American forests, are very imperfectly 
represented in our climate by the Ivy, the Honeysuckle and 
the Clematis, the Bindweed, and the Hop-plant. The stems 
of ‘which we have spoken are aerial; but there are subter- 
