266 VARIATION, DISTRIBUTION, AND EVOLUTION OF THE GENUS PARTULA 
SUMMARY AND CONCLUSION. 
In presenting a general statement of the important points of the foregoing 
detailed description, almost the same expressions could be given as in the case of 
sinistrorsa. Not only are the principles of distribution and variation identical, with 
the same significance as before, but because the whole variety is so similar in its 
general features of color-analysis and color-composition, the specific facts also are 
essentially like those demonstrated through the study of the former primary variety. 
I. The colonies of sinistralis vary from valley to valley without relation to specific 
environmental influences. Variations are displayed (a) in the relative numbers of 
the variety in the whole Partula population; (d) in the proportionate numbers of 
sinistral and dextral representatives; (c) in the color-composition of the colony, 
determined by the relative numbers assigned to the primary color-classes; and (d) 
in the intrinsic differentiation within the major color-divisions. The last-mentioned 
point is one that should receive special emphasis. 
TasBLeE 219.—Partula otaheitana sintstralis. 
Summary statistical description, sinistral shells. 
Mean value. 
Tooth, index.} 
2.6797 = .0232 
2.8926 + .0187 
3.0624+ .0158 
2.9033 + .0852 
2.9333 + .0895 
2.9671 + .0399 
2.9222 + .0279 
1.5895 = .0606 
1.6286+ .0748 
Shell. Aperture. Length aper- 
ture + length 
Valley. No. Snell, prone 
Length. Width. Proportions. Length. Width. Proportions. tions. 
mm. | mm. p. ct. mm. mm. p. ct. p. ct. 
Meohuserry: 457| 17.2636 .0244) 9.9222+.0129| 57.3665+.0681) 8.8794 .0138| 6.7639 .0110) 76.1061 = .0834| 51.3403 .0565 
Papeiti 474) 16.6684+.0236) 9.3359+.0130) 55.9346 = .0729) 8.5506+ .0129| 6.5409 .0112) 76.3439 .0794) 51.1983 .0545 
Temarua 539| 16.8495+.0207, 9.5644 .0112|) 56.6986 .0629| 8.7480+.0114| 6.7018 .0095| 76.5376 .0710) 51.8148+.0471 
Vaipoo..... 61) 17.0123 .0641) 9.6672+.0341) 56.8279+.1982 8.8574+.0354| 6.7164+.0278] 75.7459 .2280) 52.0246+.1553 
Tearatapu..| 30) 16.7000+.1096, 9.7067 .0530 58.2000 + .2625| 8.8800+.0720| 6.8467 .0547| 77.1333 .2707| 53.1667 + .2233 
Opiriroa....| 152) 18.2118+.0417) 9.9605+.0208) 54.5789+.1141) 9.2395+.0232) 7.0474+ .0184) 76.1382+.1436| 50.6316+ .0843 
@tunassse 346] 18.5546 .0294 10.2896 .0159| 55.3960 .0821; 9.5566 .0161) 7.2572 .0135| 75.9220 .0962) 51.3815+ .0664 
Maruia..... 103} 18.0209+ .0483| 10.2767 + .0234 57.0243 +.1434) 9.3427+ .0290| 7.2029 .0227| 77.0825+.1853) 51.7233+.1259 
Tereehia....| 69) 17.6109 = .0688) 9.8623 + .0326) 55.8913 .1773) 8.9667 = .0317| 6.7812 .0311| 75.6014 .2225| 50.8478+ .1532 
Tiamao....| 176) 17.8148 .0389) 10.1511 .0178) 56.9034 .1097) 9.2170 .0217| 6.9193 .0173| 74.9943 + .1313) 51.6364 .0944 
176 ae aes aoe ts| 10.5795 + .0219 cicler amas 9.6341 + .0234| 7.2568+.0185| 75.2670 .1306| 51.6022 +.0877 
1The numbers are greater in some cases, as given in the foregoing tables. 
Il. The dimensions, proportionate measures, and the columellar tooth vary from 
valley to valley, again without any consistent relation to external influences. ‘The col- 
lated average values for the several characters in all of the colonies (table 219), the 
differences considered in geographical order (table 220), and the graphic representa- 
tion (table 221), present the facts in their fullness. Intervalley migration may play 
a larger part than in the case of rubescens in keeping the colonies of neighboring 
areas more similar to one another, because the high degree of moisture and the 
growth of habitable forests at lower levels facilitate the passage from one region to a 
contiguous valley, which can not be the case in the drier portions of the island. The 
greater degree of resemblance, then, displayed by sinzstralis associations would not 
be due to more similar ecological conditions, but to a genetic interchange, as it were, 
of the congenital characteristics inherent in the emigrants. 
1.4567 + .0345 
1.0444 .0128 
