500 MAcCAUGHEY: THE STRAND FLORA 
Lepidium owathense Phyllostegia variabilis 
Capparis sandwichiana* Boerhaavia diffusa 
Portulaca oleracea Achyranthus splendens 
Tribulus cistoides Euxolus viridis 
Sicyos hispidus Chenopodium sandwicheum 
Sicyos microcarpus Santalum Freycinetianum 
Sesuvium Portulacastrum Cyperus laevigatus 
Lipochaeta integrifolia Cyperus pennatus 
Scaevola Lobelia Cenchrus calyculatus 
Solanum laysanense Sporobolus virginicus 
Ipomoea Pes-caprae Eragrostis hawaiiensis 
Ipomoea insularis Lepturus repens 
Nama sandwicensis Pritchardia Gaudichaudii 
Heliotropium curassavicum 
8. Root-Molds.—An interesting formation along the Hawaiian 
littoral, that has also been recorded from other parts of the world 
(see Dolley, ’89, pp. 131, 132; and Darwin, ’60), is the root- 
mold. This is well developed on sandy shores with persistent 
winds, where there has been considerable vegetation. The west 
end of Molokai, the Maui isthmus, Makapuu and Kaena on Oahu, 
and the Mana region of Kauai all possess notable root-mold for- 
mations. The molds are produced by the cementing together of 
the sand particles which lie near the ramifying roots of beach 
plants; the cementing process is undoubtedly due to specific root 
excretions, as well as to the percolating rain-water which follows 
the courses of the larger roots. In the course of time the vegeta- 
tion dies, the winds Sweep away the loose sand from around the 
more solid molds, and the latter are eventually exposed. They 
appear either as isolated cylinders, rising here and there above the 
sand, or as irregular masses of branching tubes. They rise to a 
height of three to twenty inches above the present level of the 
sand, and in color are white or yellowish brown. 
The lumen varies from a fraction of an inch to nearly a foot 
and is rarely open; it is more or less completely filled with lime- 
stone. The smaller sizes are the most common, as the majority 
* This abundant indigenous pseudolittoral was inadvertently omitted ito the 
list on p. 276. It isa straggling shrub, inhabiting arid rocky lowlands and beaches; 
a favorite habitat, for example, is a rocky talus slope near the sea. 
