“tent hill". Streams heading on opposite sides of such divides have approxi- 
mately the same source elevations and stream profiles. 
6. Areas of uplands are detached and surrounded by coastal plains. 
7. All relief above that of stream gradients has approximately the same 
degree of slope; and the angle of such slope remains constant (neither convex 
nor concave) regardless of the erosion stage. The angle of repose of the ter- 
rain material determines the slope of relief, and erosion is by parallel retreat. 
"Tent hills" are common; "turtle backs" are infrequent. 
8. There are no faceted hills facing the consi The only facets face 
stream valleys and are formed by ravines between knife-edged ridges, both of 
which are truncated by through flowing streams. 
9. There is no formation of talus throughout the three phases of the 
region. 
CONCLUSION 
The subtropical humid region of Japan can be considered as analogous to 
the tropical humid regions. Its humid marine climate moderates the intensity 
of rainfall even though the amount and lack of pronounced seasonal variation 
closely approximate tropical humid conditions. This factor (it may be impor- 
tant) and the more moderate temperatures are the chief distinction between the 
two climates. 
The erosion process leaves landforms of the tropical semiarid regions in 
the humid region of this study. The similarity of the present region and tropi- 
cal humid regions leads to the conclusion that erosion is by the same method 
in both the tropical semiarid and humid regions; excepting the three mentioned 
areas — arid, limestone and mountains. 
Original materials from which the soil has been formed plays no signifi- 
cant part in forming the topography. One of the few structural features in the 
vicinity consists of the remnants of a syncline (canoe shaped angles rather than 
cigar shaped) which is included as an illustration. The attitude of the members 
has been destroyed and the topographic characteristics (angle of slope, drain- 
age, vegetation, etc.) of the remnants are similar to those occurring throughout 
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