PARTULA OTAHEITANA. 
135 
TasBLe 69.—Partula otaheitana amabilis, Hamuta Valley. Analysis of the color-classes. 
Mean VALUE. 
Aperture. Length aper- 
; ____| ture+length 
Series. shell, propor- 
Length. Width. Proportions. Length. Width. Proportions. tions. 
mm. mm. p. ct. mm. mm. p. ct. p. ct. 
Sin., plain, I.) 30 18.1200+.0779| 10.6200+.0553} 58.4667 .2744| 9.4267+.0601| 7.4200 .0474| 78.3000+.3170| 51.7333+.2891 
II.| 52 | 18.3500+.1023] 10.7039+.0445} 58.2500 .2192) 9.6039 .0469| 7.4693 =.0401| 77.6731+.2520) 52.2115+.1571 
III.| 165 | 18.3591+.0456) 10.7206=.0226) 58.3727== .1175| 9.5776 .0241| 7.5158+.0206) 78.2212 .1540} 52.0818+.1000 
IV.| 36 | 18.3584+.0937| 10.7056=.0518) 57.7222 .3145| 9.5000+.0579| 7.4778+.0488) 78.7778=.3051)| 51.6111 .2132 
Sin., banded. . 6 | 18.1500+.1763| 10.9333 +.1472| 61.0000+ .8958) 9.8000 .1549| 7.7667 = .1175| 79.6667 = .6036| 53.8333 + .8804 
Sin., plain, all.| 283 | 18.3320+.0336 10.7049 = .0179| 58.3551 .0917| 9.5565+.0193) 7.4922 + .0163) 78.1996+.1140) 52.0088 .0773 
Sip Glllbsoco00 289 | 18.3282+.0332) 10.7097+.0172) 58.4100 .0928) 9.5617+.0190) 7.4879+.0160) 78.2301+.1125) 52.0467 = .0785 
Dex., plain, I.| 34 18.4205 +.0833| 10.7765 + .0452| 58.5588 .2135) 9.6647 + .0568) 7.5706 .0452) 78.2059 .3155} 52.5000 .2023 
Il.) 24 | 18.3875=.1257| 10.7750+.0609) 58.7500 .2789| 9.5917+.0818) 7.5417+.0739| 78.4166+.3394| 52.1667 +.2439 
IIl.| 88 | 18.5819 .0686) 10.8296 .0373) 58.0795 .1520) 9.6750+.0360) 7.5569 .0283) 78.0681 += .2013) 51.9886 .1382 
IV.| 18 | 18.4500=+.1558) 10.5889 .0919) 57.3333 .3820) 9.6112+.1056| 7.4223 .0842) 77.2778+.5866| 52.0000+.3056 
Dex., banded.. 2 | 18.2000 .0715) 10.8000 = .2478) 58.5000 1.4308) 9.4000+.1431| 7.2000+.1431| 76.0000 .2385) 51.5000+ .9539 
_ SS —————Sj]—S | 
Dex., plain, all.| 164 | 18.5055+.0480 10.7848+.0263, 58.1951 .1118) 9.6537-+.0287| 7.5423 .0217| 78.1610+.1510| 52.1220+.0933 
Dex., all......| 166 | 18.5018.0475| 10.7844 .0262/ 58.1988 .1118) 9.6506+.0284| 7.5386 .0216) 78.0361+.1497| 52.1144+.0929 
STaNDARD DEVIATION. 
Sin., plain, I.} 30 0.6325=+.0551| 0.4489 .0391| 2.22834 .1840) 0.4885+.0425) 0.3850+.0335) 2.5742+.2241| 2.3478+.2044 
IOI) &Y 1.0944 .0723 4764+ .0314| 2.34424 .1550) .5015+.0332| .4286+.0283) 2.6941+.1782| 1.6795+.1111 
III.| 165 -8685 + .0322 -4313=.0160| 2.2379 .0831) .4590+.0170) .3931+.0146) 2.9328+.1089| 1.9039+.0707 
IV.| 36 .8411=+ .0662 4606+ .0366| 2.8049 .2224) .5142+.0409| .4340+.0345) 2.7142+.2157| 1.8970+.1508 
Sin., banded. . 6 .6403 = .1247 -5344=+ .1041! 3.2532 .6334| .5627+.1095) .4269+.0831) 2.1921+.4268| 3.1972+.6225 
Sin., plain, all.| 283 .8390 + .0238 -4465=.0126| 2.2861 .0648) .4804+.0136| .4057+.0115) 2.8430+.0806) 1.9268+.0546 
Siny allo cocce 289 -8359 + .0235 4396+ .0122) 2.3409+ .0656| .4833+.0134) .4080+.0113) 2.8388+.0795| 1.9788+.0555 
Dex., plain, I.| 34 .7204 .0589 .3911=.0319) 1.8462 .1510) .4910+.0402) .3907+.0319| 2.7281+.2231| 1.7489+.1430 
II.| 24 -9132+ .0889 4428+ .0431| 2.0258 .1972) .5944+.0578) .3915+.0522) 2.4650+=.2400) 1.7716+.1724 
III.} 88 -9538 + .0485 .5240+.0264| 2.11442 .1075) .5016+.0254) .3942+.0200| 2.7993=.1423) 1.7254+.0977 
Iv.| 18 -9798 += .1102 .5782+.0650| 2.4095 .2701| .6641+.0746) .5298+.0595) 3.6901+.4148) 1.9221+.2161 
Dex., banded. . 2 -1500+ .0505 -5196+.1752| 3.0000+1.0117| .3000+.1012) .3000+.1012) 0.5000+=.1686) 2.0000+.6745 
Dex., plain, all.) 164 -9118+ .0339 .4999= .0186| 2.1224+ .0791| .5449+.0203) .4124+,.0153) 2.8673+.1068] 1.7712+.0660 
Dexenallernrse- « 166 -9070=.0336 -5000=.0185| 2.1353 .0790) .5433+.0201) .4130.0152) 2.8594+.1058) 1.7756+.0657 
It appears that the dextral and sinistral groups of banded specimens differ from 
the comparable divisions of unbanded shells in totally unlike ways. 
The reversed 
shells are about the same in length, decidedly wider, and very much stouter, while 
in the characters of the aperture they display greater length, greater width, and 
somewhat rounder proportions; it follows that the proportion of aperture-length 
to shell-length is much higher. 
have comparatively shorter shells and distinctively shorter and narrower apertures 
that are relatively narrowed also; the proportion of aperture to shell in length is 
less than that of the plain shells. It does not seem, then, that the direct and reversed 
shells with bands are very similar in statistical respects, or that they constitute a 
subtype that is essentially independent of the prevalent unstriped kind. Again it 
may be pointed out that if such snails are sports from the plain stock, as they appear 
to be, they would be likely to arise from parents at widely separated positions on the 
graduated scale of variation; therefore their mean in any one character would tend 
On the other hand, the dextral banded individuals 
