594 
VAUGHAN MACCAUGHEY 
5. The forest forms an almost unbroken mantle, covering the peaks, 
slopes and ravines. The only gaps are those upon the very steep 
cliffs, and the rents caused by landslides. The landslides vary in 
width from 10-40 feet and in length from 20-400 feet. At any given 
time there are approximately 125 landslide scars visible in the Manoa 
rain-forest. 
6. The foliage of the rain-forest vegetation is, in general, small, 
simple, oval, thick, coriaceous, and with a glossy upper surface. The 
prevailing color is a dark, dull, heavy green, approaching olive. 
7. The vegetation is very slow-growing, and relatively small 
shrubs and trees show that they have attained considerable age (30 
to 50 years). 
8. The undergrowth is scanty, and consists mainly of bryophytes 
and the lesser species of pteridophytes. There is practically no grass 
or annual vegetation. 
9. The flowers of the rain-forest are small and inconspicuous. 
There is no well-defined flowering season, and very few showy species. 
10. Tree-ferns and palms comprise a very minor element in the 
rain-forest. Orchids are rare. Lianas are of a relatively few species, 
and are not as abundant as in the lower forest zone. Plants along the 
summit ridges, exposed to the wind, tend to assume krumholz forms. 
11. Despite the heavy precipitation, the streams of the hanging 
valleys and ravines of the rain-forest are exceedingly inconstant in 
character, filling with great rapidity after a storm, and soon running ' 
almost dry. 
12. In the absence of definite records for the Manoa rain-forest, 
the data given by Shreve^ for the Jamaican rain-forest may be pre- 
sented as suggestive and probably very nearly the same as for Manoa: 
Temperature 
of the Soil Of the Air 
Annual mean 61.6? F. 60.8° F. 
Annual mean range 2.9° 5.3° 
The humidity of the Jamaican forest (annual summary of monthly 
means for 15 years), is 84.1 percent; Manoa conditions are closely 
comparable to this. 
20. HANGING VALLEYS 
Above the abrupt slopes and precipices that frame the valley 
head is a series of little hanging valleys. They are separated from 
2 Loc. cit. 
