274 ' 
PACIFIC SCIENCE, VoL VII, July, 1953 
TABLE 1. 
Chemical Composition of Some Saipan Soil (Analyses of 
Whole Soil, after Kawamura et al.) 
SOIL TYPE 
SAMPLE 
DEPTHS 
LOSS ON 
IGNITION 
sio2 
AI 2 O 3 
Fe203 
Cao 
MgO 
K 20 
Na20 
Inches 
Per cent 
Per cent 
Per cent 
Per cent 
Per cent 
Per cent 
Per cent 
Per cent 
"Red-colored limestone soil" 
= Saipan clay 
0- 6 
22.36 
25.62 
31.46 
14.18 
2.96 
2.10 
0.27 
0.64 
6-45 
13.10 
26.38 
40.86 
15.07 
2.63 
2.36 
0.25 
0.63 
"Yellow-colored limestone 
soil" = Chacha clay 
0- 8 
18.82 
31.99 
29.20 
15.90 
1.67 
0.12 
0.85 
8-27 
13.37 
32.32 
32.28 
15.10 
0.64 
0.22 
0.64 
"Brown-colored limestone 
soil” “ Dandan clay 
0-10 
18.98 
24.81 
35.15 
11.58 
5.86 
2.66 
0.24 
0.92 
10-33 
14.22 
15.38 
43.64 
15.91 
6.85 
1.05 
1.55 
1.03 
"Red andesitic soil" 
= Dago clay 
0-12 
14.12 
34.24 
27.57 
21.05 
0.76 
0.94 
0.17 
0.25 
12-50 
10.67 
37.95 
31.01 
17.26 
0.45 
1.25 
0.14 
0.50 
"Red tuffaceous soil" 
= Akina clay. 
0- 8 
14.02 
46.61 
19.76 
14.52 
1.21 
0.25 
0.33 
8-24 
10.33 
50.37 
24.60 
12.20 
0.95 
0.19 
0.43 
24 + 
7.52 
53.02 
23.76 
12.34 
0.82 
0.15 
0.74 
Data are abstracted from a number of analyses reported by the Japanese investigators. These analyses were carried out with 
the carbonate fusion method. 
dons and streaks which are present may be 
indicative of parent material differences or 
introduction of such material in ground water. 
Chemical analyses (Tables 1,2,3) indicate a 
silica content (whole soil) of about 30 per 
cent, cation exchange capacity near 6.5 milli- 
equivalents per 100 grams of dry soil, and a 
derived silica-sesquioxide ratio near 1.5. 
These soils differ in many respects from 
most deep soils over limestone of warmer 
climates elsewhere, such as the ”Terra Rossa” 
soils, the ”laterite” soils of Cuba and Puerto 
Rico, and the "reddish-brown lateritic” soils 
of the southern United States, but do seem 
to resemble some Puerto Rican soils as de- 
scribed by Roberts et al. (1942). They differ 
from Terra Rossa, an ill-defined group of soils 
especially common over limestones of the 
Mediterranean area (Reifenberg, 1938; Joffe, 
1949) by reason of higher organic matter 
content and lower content of bases. Many 
investigators wish to restrict Terra Rossa to 
red soils over limestone developed under a 
Mediterranean climate-^cool, moist winters 
and hot, dry summers. Red soils over lime- 
stone in the southern United States, especially 
the Dewey and Decatur series, differ from the 
Saipan and Chacha series in consistence and 
reaction (data on these American soils are 
presented by Alexander et ah, 1939). Saipan 
clay and Chacha day are more plastic and 
firm and have higher pH values, being only ^ 
very slightly acid in the subsoil. The "lat- 
erite” soil over limestone in Cuba and Puerto 
Rico (the Matan2as series) is also more friable 
and acid than these soils of Saipan (Bennett 
and Allison, 1928; Roberts et al., 1942). The 
firm soils over limestone in Puerto Rico, es- 
pecially the Coto series, appear to resemble 
the Saipan and Chacha series. 
Since the Saipan and Chacha series do not i 
have some of the important characteristics I 
described by Kellogg (1949) as criteria of | 
latosols, they are provisionally termed "lato- 
solic inter grades.” They are not highly porous 
or friable but are firm and plastic. They are 
nearly neutral in reaction which, together with 
available data from chemical analyses, indi- 
cates that they do not have low silica-sesqui- 
oxide mole ratios, extreme silica depletion, 
