197 



half-inch in diameter, and extend out into norma! leafy branches. 

 Artahotrys has stiff short hooked tips on some twigs. These 

 organs are quite few in number, but their size and strength 

 apparently compensates for their numbers. 



Other striking lianas are the great Bauhinias, with zigzag 

 stems of very unsymmetrical structure, Hippocrateas with ten- 

 drils a foot long, and the icacinaceous Phytocrene macro phylla. 

 The latter is especially conspicuous for its huge clusters of 

 flowers and fruit, borne in globular clusters a foot in diameter on 

 the old wood, and therefore exhibiting the well known tropical 

 phenomenon called cauliflory. Many other species of plants in 

 the garden illustrate the same habit, but the descriptions and 

 photographs of cauliflorous trees in Schimper's Plant Geography 

 are so familiar that further discussion is unnecessary. 



At the extreme end of this collection is a large plant of the 

 leguminous climber Derris scandens, with a basal diameter of 

 about four inches. It is wound around the trunk of a good-sized 

 tree, and branches freely on its way up. Some of these branches 

 have been completely overgrown by the tree, so that portions of 

 the climber disappear from view beneath the bark, to reappear 

 as much as four feet away. In one or two places, even, the Hana 

 has branches whose point of origin is completely covered, so that 

 the smaller stems appear to grow out from* the host tree. Neither 

 tree nor liana appear to suffer from the peculiar circumstance. 



In this section of the garden, three or more species of the epi- 

 phytic genus Dischidia, of the family Asclepiadaceae, are common 

 on trees, and show some remarkable adaptations for securing 

 their water supply. Two or possibly more of these species, all 

 without labels, have the same structure but differ merely in 

 size. In the smaller the leaves are about an inch wide; in the 

 larger, three inches. In both the leaves are orbicular or nearly 

 so, lie closely appressed at their edges to the bark of the support- 

 ing tree, and are convex on the outer exposed surface, so that a 

 free space is included behind the leaf. Here small quantities of 

 rubbish collect and doubtless hold some water, while the roots 

 which arise freely from the side of the stem penetrate this cavity 

 and absorb water from it. Such a structure is of course essen- 



