Navo shrubs are St. calaminthoides and St. scrophularioides, the latter with small 
pale yellow flowers covered with silky hair. The genus Phyllostegia, also of the 
Labiate family, has several species. Raillardia scabra is also common on the aa 
as well as Smilax sandwicensis, and several ferns, of which Pellaea ternifolia 
and Sadleria cyatheoides are the most common. And all of these in a compara- 
tively small area. Clermontia coerulea is here a fine tree, growing to a height 
of 20 feet or so, on the aa lava, shaded by Ohia and Sandalwood. 
This forest merges gradually into the great central plain at an elevation of 
5000 feet. Of course, clumps of tall trees can be found in certain localities and 
on the plateau also, as well as higher up on the slopes of Mauna Loa. The 
trees become smaller and only a few stunted Naio and Sophora trees (Mamani), 
together with Santalum, are here to be found. 
At Pulehua and beyond toward Mauna Loa a nice Koa forest, mixed with 
trees peculiar to this elevation, such as mentioned above, extends up to an ele- 
vation of 6000 feet. Hoa is the principal tree. The country is composed of 
rich, black soil, now supporting a rank growth of undesirable weeds. A most 
interesting feature in this forest is the lobeliaceous Delissea undulata. Pre- 
viously this plant has only been recorded from Niihau, Kauai and Maui, and 
that at a low elevation on exposed open cliffs, only reaching a height of 10 feet. 
Here at 6000 feet it grows under the shade of giant Koa trees on the slopes of 
the numerous crater hills with which the country is covered. The plant grows 
here 35 feet tall, perfectly straight, with a bole only two inches in diameter, not 
branching, and bearing at its apex a crown of leaves only one and a half feet 
in diameter. (See plate XVII.) These beautiful little round crowns are often 
hidden in the foliage of the Koa, so that only the gray, straight stems covered 
with leaf-sears can be seen. The plants are exceedingly numerous, but especially 
on the crater bottoms of the numerous voleanie cones, where they form the main 
vegetation. Looking down into one of these cones, one sees the tops of this 
curious plant like cabbage heads protruding up to the rim of the cone. This is 
the only lobeliaceous plant at this elevation. 
THE GREAT CENTRAL PLAIN. 
hen we step out on this great plateau from the South Kona side, we have 
Hualalai to the left, Mauna Loa to the right, and Mauna Kea in front of us. 
This great plain is composed mainly of pahoehoe lava and black cinder. The 
pahoehoe lava has often broken through, and huge caverns or eaves are visible, 
which expose again old pahoehoe lava or black cinder. The clouds gather at 
about eight o’clock in the morning around the slopes of Mauna Loa up to an 
elevation of 4000 feet, where they remain under normal weather conditions up 
to noon. At about two o’clock they encroach on to the central plateau, which 
by three o’clock is completely covered by the clouds. When eaught out on this 
plain without a compass in the fogs it is indeed exceedingly difficult to find 
one’s way. The plain is about fifty miles across and almost level, full of holes 
45 
