
Series. 
Puntan Flores: 
MUM OL Gere, a cere cbse ss 
BSICOIGEM A Ie ae ce secede 
castanea-rubescens..... 
Sadog Tase: 
REWECOLORS sip soisih sam ass» 
ie ESS) 4 oes ee 
SATS: LOS Gq alee Ce ae 
castanea-rubescens.... . 
Puntan Muchut: 
MIBAHORS op)osic sas cca s 
SHOE ete casino eh aes 
castanea-rubescens..... 
Fanaganam: 
MEREIGEOT's 5 oisetielee sivas s 
castanea-rubescens..... 
castanea-purpurescens.. 
Torre: 
castanea-rubescens..... 
Garapan: 
[2 ee) (Oe 
castanea-rubescens..... 
castanea-purpurescens. . 
Chalankiya: 
CES) OO Ses Sa 
TABLE 55.—Partula gibba, Saipan. 
No. 

Length. 
mm. 
16.9250 +.2304 
17.5869 +.0517 
17.5552 4.0352 
17.6807 +.1286 
17.7500 +.0601 
16.9144+.0271 
16.9186 +.0609 
16.4731 4.1273 
16.2720+.0551 
18.0500 +.0 
17.0568 +.0517 
17.4286 +.0842 
17.5447 +.1186 
17.1239 +.0805 
17.3833 4.1227 
17.1552 +.0356 
16.8980 +.1328 
16.2500 +.1066 
16.6229 +.0590 
16.5500 +.1593 
16.6646 +.0401 
16.4000 +.1676 
17.7676 +.1309 
17.2553 +.0234 
17.1500 
17.3520 +.0561 
17.1220 +.0376 
17.2051 +.0644 
17.0589 +.0451 
17.6900 +.0693 
16.8500 +.0953 
16.2500 +.0 
16.7676 +.0247 
16.8765 +.0551 
16.6700 +.1214 


PARTULA GIBBA, SAIPAN. 
Shell. 
Width. 
mm, 
11.9000 +.1581 
12.3500 +.0379 
12.1158+.0311 
12.2385 4.0999 
12.3286 +.0442 
12.0303 +.0228 
11.9686 +.0441 
12.4846 +.0796 
12.2729 +.0464 
13.0000 +.1431 
12.3405 +.0397 
12.4571 +.0538 
12.5105 +.0878 
12.3261 +.0600 
11.9666+.1011 
12.0756 +.0219 
12.0840 +.0678 
11.6333 +.0609 
11.8513 +.0425 
11.5800 +.1246 
11.8000 +.0310 
11.8000 +.2361 
12.5941 +.0919 
12.0752 +.0180 
11.9000 
12.3857 +.0410 
12.2614 +.0294 
12.3286 +.0538 
12.3571 +.0425 
12.3667 +.0811 
11.7666 +.2044 
11.1000+.0 
11.6211 +.0163 
11.7566 +.0325 
11.5666 +.0667 


MEAN VALUE. 
Proportions. 
D. ct. 
72.0000 .7350 
70.0761 +.1456 
68.9298 +.1365 
69.1923 +.3623 
69.4388 +.2017 
71,0479 +.0825 
70.5428 +.1532 
71.1154+.3635 
70.9407 +.1365 
72.0000 +.7154 
72.2703 +.1668 
71.2500 +.2518 
71.3947 +.2835 
72.0217 +.2012 
68.5556+.3244 
70.2840 +.1070 
71.6600 +.3021 
71.5000 +.15 89 
71.2571 42.1520 
70.3000 +.4938 
70.6528 +.1293 
71.5000 +1.1923 
70.8529 +.4556 
69.9130 +.0836 
70.5000 
71.3163 +.2084 
71.5467 +.1279 
71.6244 +.2000 
72.3214 +.2030 
69.9667 +.4163 
68.8333 £.9712 
68.5000 +.0 
69.2990 +.0734 
69.6239 +.1392 
69.3666 +.3412 


Length. 
mm. 
9.6500 +.1678 
10.0870 +.0302 
9.9562 +.0237 
10.1000 +.0639 
10.1898 +.0352 
9.6448 +.0147 
9.6714 +.0354 
10.0538 +.0765 
9.9588 +.0311 
10.2000 +.0447 
9.9514 +.0297 
10.1214 +.0502 
10.2368 +.0631 
9.9435 +.0469 
9.7555 +.0668 
9.6868 +.0172 
9.6680 +.0584 
9.2666 +.0668 
9.6714 +.0337 
9.4800 +.1013 
9.4945 +.0227 
9.7500 +.1744 
10.1237 +.0717 
9.7974 +.0125 
9.9000 
9.9245 +.0300 
9.8400 +.0217 
9.8429 +.0410 
10.0214 +.0324 
10.2200 +.0593 
9.6333 +.0734 
9.7000 +.0954 
9.5173 +.0126 
9.5814 +.0300 
9.1000 +.0577 


Aperture. 
Width. 
mm, 
7.3000 +.0954 
7.4391 +.0249 
7.2895 +.0215 
7.4692 +.0654 
7.4798 +.0292 
7.1291 +.0132 
7.1943 4.0281 
7.3923 +.0715 
7.3576 +.0282 
7.7000 +.0954 
7.4189 +.0237 
7.5286 +.0504 
7.6789 +.0540 
7.3087 +.0418 
7.2333 +.0653 
7.2345 +.0125 
7.2840 +.0381 
7.0333 +.0259 
7.2115 +.0258 
7.0600 +.0911 
6.9736 +.0187 
7.1500 +.1536 
7.6882 +.0687 
7.3554 +.0099 
7.5000 
7.3735 +.0251 
7.2480 +.0185 
7.2378 +.0337 
7.3893 4.0287 
7.3000 +.0492 
6.8333 +.0734 
6.9000 +.0 
6.9621 +.0101 
7.0168 +.0208 
6.9400 +.0420 



Statistical description of the color-classes (in part). 
Proportions. 
p. ct. 
75.2500 +.4976 
73.7717 4.1613 
73.3333 +.1412 
73.7307 +.3962 
73.2959 +.1936 
73.8448 +.0872 
74.4143 4.1950 
73.6538 +.4205 
73.8729 +.1533 
75.0000 +.1923 
73.5946 +.1558 
72.1786 +.2386 
75.0263 +.4090 
43.3091 .3273 
73.4445 +.3200 
74.5801 +.0845 
75.3800 +.3311 
75.1666 +.4680 
74.3429 +.1906 
75.1000 +.5895 
73.4028 +.1205 
73.5000 +.6745 
107 

Length aper- 
ture + length 
shell, propor- 
tions. 
p. ct. 
57.2500 +.3675 
57.1957 +.1004 
56.6053 +.0984 
57.0385 +.3250 
57.3776 +.1624 

56.9061 +.0593 

57.0571 +.1452 
57.1154 +.2699 
57.3813 +.1294 
57.0000 +.2384 
58.2433 4.1334 
57.8215 +.1671 
58.2895 +.1708 
58.0217 +.1801 
56.1667 + .2596 
56.3363 + .0871 
57.3000 +° 2158 
57.3333 + 3700 
58.1143 + 1411 
56.9000 +.3594 
56.8680 +.0986 
58.7500 +.9650 
75.5588 +.4179/57.0294 +.2578 
75.0339 +.0771 
74.5000 
73.6800 +.1215 
73.5415 4.2022 
73.6607 +.1902 
71.7000 +.3773 
70.8333 +.1836 
71.0000 +.7154 
72.9377 +.0357 
73.4646 +.1257 
73.3000 +.3617 
56.6593 4.0653 
56.5000 
74,1122 +.2610/57.1326+.1427 

57.3400 +.0868 
57.0307 +.1594 
98.5357 4.1523 
57.7667 +.3333 

55.8333 4.1836 
53.0000 +.2384 
56.3143 +.0535 
56.3053 +.1151 
56.2333 4.2229 

shell length with the whole local assemblage of which, naturally, they are both com- 
At Puntan Flores, bicolor is average, while the dark class is composed of 
longer shells; at Sadog Tase the former is again average, but the latter shows a 
ponents. 
very much lower figure. 
At the next station of Puntan Muchut both classes 
are noticeably shorter than their associates and bicolor is especially so; but at 
Fanaganam the former is longer and the latter is shorter, in comparison with the 
general colonial average. 
It is not necessary to complete the sequence to realize 
that the structural character in question varies independently of the color qual- 

