Valley. 
Tuauru... 
Ahonu..... 
Papenoo.. . 
Faarumai.. 
Tiarei..... 
Mahaena.. 
Paraura... 
Papeiha... 
Utuufai. . 
Haavini... 
Tautira.... 
Aiurua.... 
Utuufai... 
PARTULA OTAHEITANA. 183 
IV. The relationship between the constituent color-classes of a single valley associ- 
ation 1s closer than the relationship between any one of them and its counterpart in a 
neighboring valley. The statistical data and their graphic representation give the 
basis for this generalization. In addition, it has been shown that adults of a 
primary color-class produce offspring of their own kind and of contrasted types as 
well; certainly, therefore, close genetic bonds exist between snails with differently 
colored shells, which snails live in one and the same valley. 
TasLe 116.—Partula otaheitana rubescens. Progressive comparison of valley colonies, in geographical 
order. Differences in mean values. 
Shell. Aperture. Length aper- 
ture + length 
shell, propor- Tooth, index. 
Length. Width. Proportions. Length. Width. Proportions. tions. 
mm. mm. Pp. ct. mm. mm. D. ct. p. ct. 
+1.1603+.1436 | +0.7666= .0932 |[+0.6379 + .4328]| +0.5766+.0806 | +0.5412+.0528 [+.03129+ .4858][+0.2836+.4159]) +1.1559=+.1038 
= 2838+ .0630 |[— .0142+.0361] + .7311+.1557 |[+ .0514+.0346][— .0668+.0290] — .9111+ .1895} +1.0051+.1242 |[+ .2019+.0770] 
jit -1630+.1423]) + .5554+.0930) +2.2889+.5296| + .4352+.0716) + .5059+.0650 | +1.9206+ .3994) +1.5731+.3209 | —1.4828=+.0371 
\ — .5562+.1874 |[— .2111+.1174][+ .6421+.7326]| — .4899+.0874) — .3053+.0798 [+ .4526+ .6555][— .9368+.3889]|[+ .0667 + .0434] 
\ —1.4000+.1813| — .4800+.1014 [+1.7000+.7488]| — .4066+.0857 | — .3333+.0715 [— .7333+ .7922]) +1.7000+.2689 | +2.6000+.2097 
f + .5712+.1491} — .3229+.0842| —3.3202+.5671 |[— .0768+.0770][+ .1041+.0589]] +2.2434+ .6132 |) —1.9382+.1911 | —1.6891+.2155 
} + .9775+.0969| + .4418+.0493 [— .4969+.2172]) + .4002+.0502 | + .1499+.0383 | —1.5948+ .2471 |[— .4717+.1704]| — .9687=+.0663 
[— .1820+.1362][— .0656+.1226][— .4829=+.8565][+ .0699+.0944]) — .3207+.0970 [3.1153 1.2688][-+ -5099 + .2640]|[— .0089= .0060] 
(— .2724+.1289]|[— .2845=.1204]|[— .0551+.8516]| — .2787+.0915 [+ .1486+.0949][+2.9542+1.2617][— .3334+.2562]| 0 
+ .5846+.0680} + .9499+.0423 | +3.1112+.1974) + .5285+.0399| + .6050+.0338 | +1.8336+ .2207| +1.1114+.1577 0 
[+ .0508+.0812]) — .1854+.0462] —1.0544+.2224| — .2165+.0416| — .3133+.0369 | —1.2399+ .2408| —1.1679+.1715 0 
+2.8806+.1291 | +1.6749+.1203 |[+ .8074+.8497]] +1.2665+.0914 | +1.1662=+.0950 |[+1.5022+1.2624][— .5963+.2521]} 0 
1Oopu as compared with Utuufai. 
V. The red and yellow ground-colors seem to bear a Mendelian relation to one 
another in inheritance, the former being dominant. 
of Mendelian heredity in these characters can not be given without experimental 
evidence, the facts in most cases are in essential accord with such an interpretation. 
Where there are sufficient data, the relative numbers of the two classes are in equi- 
librium. The heredity of ground-color is alternative in all cases. Proceeding on 
the assumption that red color is dominant to yellow, an analysis of the group dis- 
playing the latter character gives the means for testing the correspondence between 
expectation and empirical observation in the case of the alternative group, with 
general agreement as the result. 
VI. Combining the statistics for the several colonies, a collective description of the 
primary variety 1s obtained which serves for a precise comparison of P. otahettana 
rubescens with other major divisions of the species. “here are two modes of combining 
the colonial statistics so as to derive this collective description, and each mode has 
Although the final demonstration 
