PICKERING. LUNAR AND HAWAIIAN PHYSICAL FEATUKKS COMPAUKD. 105 
found upon these original floors. Indeed they rarely occur in craters of less than 
four miles in diameter. Longomontanus and another crater known as Pitatus present 
the very unusual phenomena of eccentric internal peaks. Equally striking is the fact 
that in each case the peak is found in connection with a dark floor. The explanation 
in both cases is probably that the lava, after dissolving the original floor, had begun 
to dissolve the peaks, which were pushed by the lava currents to one side, where 
© 
d solidification set in before the process was completed. In both 
cases the peaks are unusually small in proportion to the size of the craters, a> would 
naturally be the case if they had been floating partially submerged in the lava. 
Central peaks are seldom found in the Hawaiian craters, probably because the 
latter are so small. The best illustration seen was that of the small crater already 
mentioned at the northern base of Mauna Loa, about eight miles west of the Humuula 
sheep ranch, i p. 171. Unfortunately we could not get within a mile of it, but it 
seemed to be .well defined. Its diameter was thought to be about 450 feet. The 
walls were red, and the central peak dark brown. The height of the peak was the 
same as that of the walls. Another small crater two or three hundred yards back 
of Mr. Maguire's at Huehue in Kona showed a smooth central peak 15 feet in height. 
It was completely grass grown. One or two of the small craters on Hualalai, 
Jc p. 171, showed the same formation. The peaks were never pointed, but sandy and 
rounded as in the slag crater shown in Figure 11. A crater containing a central 
peak or craterlet is said to exist half a mile beyond the sixth crater near Kilauea. 
Near the centre of Haleakala is found a straight, narrow ridge, 150 feet in height by 
400 feet in length, along its crest. Its sides slope at an angle of about 30° and it is 
composed apparently of gravel and scoria. At its eastern base is the cave where 
parties sometimes pass the night. Although not especially conspicuous among the 
crater cones which dot the floor, some of which are 500 feet in height (see Figure 3), 
it seems to be unique in shape, running lengthwise of the crater. It is also almost 
exactly central in position. In passing it may be stated that the maps of Haleakala 
give a very erroneous impression of the shape of its floor. The floor at the Koolau 
and Kaupo gaps falls off sharply, showing the outline of the true floor to be not 
S-shaped, but elliptical, and extending nearly due east and west. It is an ellipse 
of great eccentricity, the length of the floor being about four times its breadth. 
Figure 18 represents a portion of the middle crater of Mokuaweoweo. Somewhat 
nearer than the centre is shown an active cinder cone composed apparently of a 
medium-sized crater and two or three smaller ones upon its rim. We were not able 
to visit it. Like the craterlets found in Haleakala, it reminds us of those found in 
