2. There have been several flows of lava from it on the open side. (a) . From the broadest part, between Puu Enuhe and Makanao. It is of aa, and has flowed down to the sea between Punaluu and an older similar stream toward Honuapu. It is evi dently comparatively recent, though not recognizable in the legends of the oldest inhabitant. It can not have been active less than two centuries ago. (b) A small aa flow starts from the cliff on the west side of the gulch flanking Makanao on the west. It does not reach quite to the stage road at Hilea. It is very olivinitic and has issued from under the later pahoehoe which overlies the yellow ash in the immediate neighborhood (c) An other aa stream, still farther west, is about one mile wide where it crosses the road. It issued from the cliff on the west side of Makanao, but from between two spurs of the older pahoehoe. Following this the road traverses a mile of pahoehoe before com ing to (d), the last aa flow, one and a half miles wide, reaching to a short distance east of the sugar mill at Honuapa. The older aa streams are covered by large kukui trees (Cordia), with their characteristic lighter yellow green color, rendering them con spicuous.
3. The greatest peculiarity in Mohokea consists in the pres ence of two parallel lines of faulted blocks running northwest from the southeastern edge. The one on the east is known as Puu Enuhe, rising precipitously along the edge of the cliff to the height of 2,327 feet. This is the most conspicuous of all the blocks and is the one most like the buttes of the Rocky Mountain region. The ridge behind the outer block falls away gradually for nearly three miles, and then rises again abruptly to Kulua, only to fall away again as at first, and reaches nearly to the inner most wall of the caldera. Viewed from a distance on either flank, the ridge resembles a huge worm with a great head and a swelling near the caudal extremity. This resemblance caught the attention of the early Hawaiians, who recite an interesting legend respecting its To the west of Puu Enuhe lies a valley one and a half miles wide. It is inhabited by Hawaiians who exhibit characteristic features of the life of the olden time. They are highlanders as contrasted with lowlanders. On the west side the valley is flanked by stupendous blocks, of which the first is Makanao, estimated to exceed 3,500 feet in height. It is hardly separated from Pakua,
as delineated upon the Government map of Hawaii, 1901. A broader notch separates Pakua from Kaiholena, 3,824 feet high. There are five blocks in this row, into the last of which a tunnel has been driven two hundred feet in quest of water for irrigation. The east side of this line of blocks is quite precipitous, repre senting the place of a fault. Both the lines of blocks have been elevated, as indicated in the figure, their altitudes being greater than that of the adjacent territory. The lowland between the elevated blocks and the east side rises gradually to the steep wall behind, toward Puu iki. The land is not cultivated for most of the distance, and is covered by the original forest of tree-ferns, ohias, and other hardwood trees, similar to those seen on the Volcano Road in Olaa. On the west side of Pakua may be seen the bed of a mountain torrent, usually dry, but often too full of water to be safely forded. This skirts the eastern border of an other lowland area like those already mentioned, save that it is cultivated and used for pasturage. It is over a mile wide and has a floor of fresh looking pahoehoe, sloping gradually to the edge of the frontal escarpment, about 1,200 feet high. Erup tions of as have proceeded from this edge along the whole width of the caldera.
The Enuhe and Kaiholena ridges are higher than the slopes of the Mauna Loa basalt opposite them, of which it is supposed they once formed a part. Hence the lowland depressions can not be regarded as the results of canyon erosion ; they probably were depressed, while the blocks were elevated. Following the defini tion of the caldera, it may be said that portions of the mountain crust were dropped, while other sections were elevated. Its de velopment was arrested. The making of the caldera was incom plete. Possibly the great size of Mohokea, comprising thirty square miles, while Haleakala is only nineteen, may have mili tated against the thorough fusing of the entire bulk.
If these blocks had been left stilted upon their ends, they would be analogous to the obelisk of Mount Pelee in Martinique. Per haps they had a similar origin.