40 
VARIATION, DISTRIBUTION, AND EVOLUTION OF THE GENUS PARTULA. 
object of making such comparisons is to discover whether an ecological condition 
can be found which directly determines the size or shape of the shells in a given 
instance; the result is always negative, as a single illustration will indicate. Within 
the arbitrary bounds of the South Central Region the habitable areas are identical 
Series. 
Northeast Region: 
Tarague..... 
East Central Region: 
Barrigarda... 
Dededo...... 
SAatciOsesdcee & 
Whole region!.... 
Coast Central Region: 
Anieuac.o.i. 
Presidio, outer 
Whole region!.... 
South Central Region: 
Ylig, lower... 
Ylig, upper... 
Pago River... 
Pago, north.. 
ontit:: Sear. 
Fonte i22!.)-13 
Whole region 
Apra Region: 
Cabras, east.. 
Cabras, west 
Whole region 
West Central Region: 
Salifantusene: 
Southwest Region: 
Umatac Salonga.... 
Umatac Pajom 
Umatac Madog..... 
Merizo.- 4. 
Whole region 
Southeast Region: 
Inarajan..... 
Whole island 

——— | | | | | | 


Length. 
mm, 
0.7511 +.0470 
-6167 +.0627 
-7716 +.0306 
-7004 +.0442 
-7598 +.0240 
.5904 +.0462 
-5813+.0591 
-6476 +.0249 
-6714 +.0230 
-7113 4.0678 
-6598 +.0763 
-8809 +.0640 
.6475 +.0630 
-5607 +.0408 
-4349 + .0423 
-6064 +.0616 
-7581+.0086 
-6959 +.0324 
-7320 +.0420 
-5189+.0218 
| | | | |S 
-7916+.0217 
-7656+.1101 
-7052 +.0462 
-7975 +.0512 
1.2039 +.0498 
-6583 +.0377 
-9934 +.0265 
-7191 +.0556 
1.0512 +.0133 


Shell. 
Width. 
mm. 
0.4244 +.0266 
-5533 +.0562 
-3840 +.0153 
.3290 +.0208 
3971 +.0125 
4231 +.0331 
.3213 +.0326 
4724 +.0255 
-3845 +.0131 
-2913 +.0278 
4589 +.0531 
-4865 +.0353 
-4038 +.0393 
-2948 +.0214 
-3326 +.0324 
-3594+.0365 
-4199+.0101 
-4043 +.0188 
4647 +.0245 
-4898 + .0206 
4559 +.0215 
-4033 +.0580 
4775 +.0312 
-4815 +.0310 
-6760 +.0279 
4323 +.0248 
5728 +.0152 
4865 +.0376 
-6259 +.0079 


Proportions. 
p. ct. 
1.8726+.1172 
2.2438 +.2281 
2.2427 +.0891 
2.0424 +.1290 
2.2566 +.0713 
1.9813 +.1553 
2.2100 +.2247 
—_——— | | ee | — 
2.4185 +.1306 3456 +.0187 
1.7821+.0611 
2.0591 +.1963 
1.5135.1751 
1.8801 +.1367 
1.8023 +.0781 
1.7399 +.1265 
1.4288 +.1391 
1.4892 +.1514 
1.9281+.0464 
1.8928 +.0881 
1.7048 +.0978 
2.1968 +.0925 
2.0581 +.0565 
1.6818 +.2418 
2.1927 +.1436 
1.9855 +.1277 
2.1410 +.0885 
2.3425 +.1345 
2.1931 +.0585 
1.9131+.1480 
2.2147 +.0281 
Length. 
mm. 
0.4290 +.0269 
4773 +.0485 
.3788 +.0150 
.3730 +.0235 
-4058 +.0128 
4274 +.0335 
.2949 +.0300 
-4148+.0224 
-3693 +.0126 
3997 +.0381 
+3852 +.0445 
-4810+.0350 
3865 +.0376 
-3427 +.0249 
-2846 +.0277 
.3113+.0316 
-3909 +.0094 
3754 +.0174 
.3693 +.0212 
4286 +.0180 
-4030 +.0110 
-3814+.0547 
-4470 +.0293 
-4202 +.0270 
-7478 +.0309 
3/22 +.0213 
.5814+.0155 
3605 +.0278 
-6050 +.0076 
Aperture. 
Width. 
mm. 
0.2935 +.0184 
-4041+.0411 
.2797+.0111 
-3114+.0196 
-3028 +.0095 
-3239 4.0254 
-2461 +.0242 
-2672 +.0092 
-2562 +.0244 
.2981+.0344 
-3339 +.0242 
-2847 4.0277 
-2191+.0159 
-1985 +.0193 
-1984+.0201 
.2829 +.0068 
-2940 +.0136 
.2921+.0167 
3335 4.0141 
.3122 +.0085 
-2328 +.0334 
3592 +.0235 
.3777 4.0242 
-4732 +.0196 
-2713 +.0155 
-4048 +.0108 
-2825 +.0218 
4293 +.0054 
Proportions. 
PD. ct. 
1.8714+.1171 
2.1804 +.2217 
1.9812 +.0787 
1.8203 +.1150 
————e 
2.0665 +.0653 
2.1229 +.1664 
1.3817 +.1405 
2.1753 4.1174 
1.8529 +.0635 
1.9976+.1905 
1.5248 +.1763 
1.8973 +.1379 
1.4085 +.1371 
1.8047 +.1312 
1.5473 +.1506 
2.1359 4.2171 
1.9665 +.0474 
1.5548 +.0723 
1.6676 +.0957 
1.8146+.0765 
1.9385 +.0532 
1.3667 +.1965 
1.8393 +.1205 
1.8411 +.1182 
2.1491 +.0889 
1.8141 +.1041 
2.0251 +.0540 
1.7159 +.1327 
2.0916 +.0265 
TABLE 14.—Partula radiolata, Guam. Statistical description: standard deviations of the fundamental characters. 
Length aper- 
ture + length 
shell, propor- 
tions. 
p. ct. 
1.7306 +.1083 
1.3205 +.1343 
1.7538 +.0697 
1.7062 +.1077 
1.9135 +.0604 
1.3876 +.1087 
1.4438 +.1468 
1.5026+.0811 
1.3722 +.0471 
1.6030 +.1529 
1.5362 4.1777 
1.8813 4.1368 
1.4529+.1414 
1.4931 +.1086 
1.5473 +.1506 
0.9989 +.1015 
1.6814+.0405 
1.5169 +.0705 
1.6900 +.0970 
2.0434 +.0861 
1.9518 +.0535 
1.2984 +.2879 
2.2144 +.1450 
1.4507 +.0932 
1.8266 +.0755 
1.2569 +.1066 
2.0198 +.0538 
1.7982 +.1391 
1.9621 +.0249 

1Including the smaller local collections. 
in botanical ecology, so far as observation goes. The shells of the high ground at 
Macajna and Fonte are short as compared with those of Ordot, which is equally 
high above the sea. With the descent to the Lonfit River locality, the length dimin- 
ishes with a definite statistical difference; but passing eastward to the Pago River 
area which is still lower, the length increases, again to a certainly significant degree. 

