276 
VARIATION, DISTRIBUTION, AND EVOLUTION OF THE GENUS PARTULA. 
result was obtained (cf. especially Pirai and Papenoo); here again the interpretation 
is suggested that more severe conditions obtaining in the lowlands eliminate the 
smaller and weaker individuals. 
Series. 
Yellow, 1906 
Red, 1906.. 
All, 1906... 
Yellow, 1907 
Red, 1907.. 
Brown, 1907 
All, 1907... 
No. 
TaBLeE 231.—Partula otaheitana crassa occidentalis. 
Length. 
mm. 
17.9675 + .0941 
17.8571 .1028 
17.9206 + .0699 
Shell. 
Width. 
mm. 
10.1900 + .0424 
10.2143 + .0637 
10.2000 + .0362 
Mean VALUE. 
Proportions. 
p. ct. 
56.0750 .2665 
57.0715 + .2978 
56.4559 + .2020 
INI osc00000 
Yellow, 1906 
Red, 1906.. 
All, 1906... 
Yellow, 1907 
Red, 1907 .. 
All, 1907... 
17.6000=+.1001 
9.9055 + .0454 
56.3334 + .2808 
32) 17.9000 + .1019] 10.1375+.0557| 56.5313 + .3032) 9.1375+.0570} 6.9500 .0417 
1} 18.35 10.30 55.50 9.14 7.10 
69| 17.7500+.0717| 10.0188= .0364| 56.4131+.2035) 9.0739+.0422] 6.8826 .0299 
137} 17.8354 .0503} 10.1088+ .0262| 56.4489 .1438] 9.2693 += .0308] 6.9555+.0218 
STANDARD DEVIATION. 
40) 0.8823+.0665| 0.3973+.0300) 2.4989 .1884) 0.4645+ .0350} 0.3872+ .0292 
28 -8066 = .0727 4999+ .0450} 2.3365+.2106| .4861=+.0438) .3502+.0315 
68 -8549 + .0494 4426+ .0256| 2.4700+.1428) .4735+.0273} .3754+.0217 
36 -8902 = .0708 4041+ .0321| 2.4980+.1985| .5487+.0436 3898+ 0310 
32 8551+ .0720 4675+ .0394| 2.5430+.2144| .4781+.0403} .3500=.0295 
69 .8827 = .0507 4483+ .0257| 2.5064 .1439} .5196+.0298} .3679+.0211 
137 .8729 + .0163 4545+ .0185} 2.4947 .1017) .5349+.0218| .3788+.0154 
TaBLE 232.—Partula otaheitana crassa occidentalis. 
Length. 
mm, 
9.4650 + .0495 
9.4714+ .0620 
9.4676 .0387 
Aperture. 
Width. 
mm. 
6.9900 = .0413 
7.0857 + .0446 
7.0294 + .0307 
Proportions. 
p. ct. 
75.0500 + .2930 
74.6785 + .3492 
74.2500 + .2263 
9.0056 + .0617 
6.8167 + .0438 
75.3888 + .2924 
75.9687 + .2732 
75.50 
75.6594 .1980 
74.7599 + 1561 
2.7472 + .2072 
2.7393 + .2469 
2.7673 + .1600 
2.6014 .1600 
2.2911 .1932 
2.4387 + .1400 
2.7098 + .1104 
1The numbers are, respectively, 40, 29, 69; 38, 34, 1, 73; 142. 
Series. Records rexel 
Aoua, yellow........... 295 213 
rete Porc Gute 318 242 
DOWD aes 5 3 
Aouay ally ce sisrexcisieeisyete 618 458 
Papehue, 1906......... 8 2 
Papehue, yellow, 1907... 31 9 
red 1907 35 16 
brown, 1907... 1 0 
Papehue, all, 1907...... 67 25 
No. of | Percent | No. of 
gravid. | eggs. 
72.2 367 
76.1 419 
60.0 3 
74.1 789 
25.0 3 
29.0 13 
45.7 24 
0 
37.3 37 
No. of Total Average 
young. | contents. | for gravid. 
116 483 RO 
114 533 2.20 
1 4 1.33 
231 1,020 2} 228) 
3 6 3.00 
5 18 2.00 
4 28 1.75 
9 46 1.84 
Aoua and Papehue Valleys. 
Papehue Valley. 
Length aper- 
ture + length 
shell, propor- 
tions. 
Pp. ct. 
§2.5750+ .1622 
Tooth, index.! 
1.6000 = .0666 
53.2857 + .2230) 1.6207 + .0895 
52.7059 .1455 
51.1112 + .2237 
51.0940 + .1997 
51.50 
51.1087 +.1490 
51.9015 + .1139 
1.5207 +.1147 
1.7496+.1577 
1.7786+ .1029 
1.9900 .1581 
1.6746 .1412 
1.8354 .1053 
1.9759+ .0805 
Fecundity. 
Average 
for all. 
The pillar tooth is developed to different degrees in the two associations. 
addition to the differences indicated by the diverse averages of the tables, we may 
cite the fact that only 73 out of 650 in the Aoua colony lack some growth, while 71 
out of 143 from Papehue are devoid of any trace of the feature. 
1.6087 + .0539 
1.7105 + .0829 
1.6471+.1116 
1.0 
1.6713 + .0680 
1.6409 + .0437 
0.6244 .0471 
-7150+ .0633 
-6641 = .0381 
-7577 + .0586 
-9648 + .0789 
-8609 + .0481 
-7722 = .0309 
In 
