TOPOGRAPHICAL, ECOLOGICAL, AND TAXONOMIC NOTES. 295 



on the weak root system, whose limited area of activity is 

 not conducive to the accumulation of either food con- 

 stituent, or water supply. The rigid, flattened flower stem, 

 is structurally adapted to carry the heavy panicles of fleshy 

 flowers. 



Its frequent associate on the dune, Hibbertia volubilis 

 Andr., is a trailer, or twining climber, as befits the situ- 

 ation. When growing on the ridges and spurs of the broken 

 dune front, its running stems turn inwards and become 

 interwoven, building up the plant into a hummocky form. 

 On the protected slopes at the rear, its movements are less 

 restricted, and it here assumes a diffuse, or scrambling 

 habit. Bentham, Fl. Austr. i, 37, notes this species as 

 climbing to a height of 2-4 feet, but under the dense 

 canopy of a close shrubbery, such as that afforded by a 

 grove of "Coast Tea-tree," its climbing habit is fully 

 developed, and in such, a habitat on the shore of Botany 

 Bay, it was noted ascending the Tea-tree to a height of 

 12-15 feet in search of the light. It has a coastal range 

 from Milton, north into Queensland, but has only'succeeded 

 in ascending the dividing range, in New England, where it 

 has reached the tableland. In the Port Jackson district 

 it extends inland to Parramatta. 



A congener, H. diffusa R. Br., a prostrate, twiggy shrub, 

 occasionally ventures on the dune flats, but its greater 

 frequency on the grasslands and hillsides, removed from 

 the littoral, demonstrates its preference for such situations. 

 At this (northern) end of the beach, Convolvulus soldanella 

 L., a sea coast habitue in most extratropical countries, is 

 sparsely represented. To secure stability in the mobile 

 sand, it has developed an intricate system of subterranean 

 creeping stems, (stolons) radiating from the rootstock, 

 upon which it depends for fixity of tenure. It will occasion- 

 ally descend the frontal embankment, where the gradient 



