DENDUM SENT
8. Lateral planation may be indicated by stream positions at the base
of valley walls but there is no steepening of walls through this process; nor
does the frequency of this occurrence indicate that lateral planation is more
than incidental. (Stream position, at the base of relief, is a savanna charac-
teristic and has nothing to do with lateral planation in these instances.)
PLAINS AREAS
Plains areas extend into the interior with a gradient suggesting that the
groundwater table determines their elevation. Although the coastal plains com-
monly have a uniform slope there are remnant swells resulting from the reduc-
tion of outliers of uplands. Fig. 3 shows the final reduction of such an outlier.
When completed the underlying plains area will form a swell in the plains sur-
face. In contrast to true coastal plains, the following characteristics are
noted for these areas.
l. Stream sources may not be related to the fragmented remains of di-
vides, and the uplands are increasingly intersected by low gradient streams
with the same valley characteristics as previously mentioned.
2. The entire lower courses of rivers flow through a broad plain of low
and uniform slope. Distributaries dissipate among rice paddies, interflow with
drainage from other large streams, or rejoin the master stream. The large
amount of surface flow contrasts with evidence of flow as seen in the uplands
and in the upper stream reaches. Tributary heads are short distances apart
and separated by no perceptible divides.
3. All streams flow on the surface of the terrain, there being no stream
terraces, levees, or indications of flood plains.
4. There is no meandering but streams often deviate from apparent logi-
cal midvalley locations. Deviations to contact the base of relief, rising from
the plains floor have been called "too often to be merely fortuitous. t 27 Bends
of smaller streams are not in smooth curves; but have an angular appearance.
5. Enclaves of coastal plains appear at the flanks of upland areas and
may be separated from other enclaves by a range of hilis , Or by a single narrow
