98 VARIATION, DISTRIBUTION, AND EVOLUTION OF THE GENUS PARTULA. 
TasLe 44.—Partula nodosa leva. Maruapoo Valley. 
MEAN VALUE. 
Shell. Aperture. Length aper- 
ture + length 
Group. No: shell, propor- 
Length. Width. Proportions. Length. Width. Proportions. tions. 
mm. mm. p. ct. : mm. mm. p. ct. Pp. ct. 
Sin., plain, 1907....) 20 | 15.5900+.1292) 9.4200+ .0534) 60.4000 + .3266) 8.4200 .0591) 6.7900 .0560) 80.5000+.4130) 53.9000 = .2356 
Sin., banded, 1907..} 31 | 15.8145=.0879) 9.5129 .0424| 60.2420+.2363) 8.4939= .0474) 6.8032+.0379| 80.2097 = .3443] 53.4678 .1909 
Sin., plain, 1908... .} 430 | 15.5418 .0234) 9.3256+.0132) 59.9991 = .0788) 8.0991 = .0127) 6.3703+.0111) 79.3372 .0959| 51.8814 .0569 
Sin., banded, 1908. .| 168 15.5160 .0400) 9.3381 .0213) 60.1310+.1296) 8.2000+.0200| 6.3250+.0216) 79.2678=.1740| 52.7262+.0901 
Dex., plain, 1908...| 17 15.7911+.1327) 9.2530 .0749| 58.4412+.3148) 8.2412 .0799| 6.3824 .0550| 77.5000 .4627| 52.2295 .2441 
Dex., banded, 1908.} 11 | 15.3227=£.1811) 9.1728 .0922| 59.6819 .5117| 8.1363+.0881| 6.3728+.0800) 78.4091 = .6457| 53.0455+.3641 
| —— 
Sinsyalls19 0a 51 | 15.7264 .0744| 9.4804 .0333| 60.3039+.1926| 8.4647 + .0372) 6.7980 .0317| 80.3235 .2650) 53.6372+.1496 
Si, alll, IOS, oo50¢ 598 | 15.5346+.0202) 9.3291 .0112| 60.0218 .0671) 8.1274 .0108) 6.3576 .0100) 79.3178 = .0853| 52.1221+.0495 
Dex., all, 1908..... 28 | 15.6071 .1113) 9.2215 .0583] 58.9286+.2879) 8.2000 .0599| 6.3786+.0459| 77.8572 +.3560| 52.4286 .2070 
Sin: wall S509 aera 649 | 15.5497+.0196) 9.3409+ .0107| 60.0439 .0642) 8.1539 .0107| 6.3922+.0100| 79.3968 .0812) 52.2412 .0484 
STANDARD DEVIATION. 
Sin., plain, 1907....} 20 0.8569 .0913) 0.3544 .0377) 2.1656 .2309| 0.3919+.0418) 0.3713+.0396| 2.7386+.2920) 1.5620+.1666 
Sin., banded, 1907..} 31 .7261+ .0621} .3499.0300) 1.9505+.1671} .3915+.0335} .3126+.0268) 2.8420+.2434) 1.5757=.1350 
Sin., plain, 1908... .| 430 .7204+ .0165| .4069+.0093) 2.4358+.0557} .3913+.0090| .3402+.0078) 2.9651+.0678) 1.7583+.0402 
Sin., banded, 1908. .| 168 -7696=+ .0283) .4105+.0150) 2.4917+.0916) .3854+.0141) .4153+.0153) 3.3433+.1230) 1.7310+.0637 
Dex., plain, 1908...| 17 -8111+.0938) .4577+.0529) 1.9242+.2226| .4887+.0565| .3363+.0389| 2.8284 .3272) 1.4923+.1726 
Dex., banded, 1908.} 11 -8904+.1280) .4534.0652) 2.5161 .3618) .4333+.0623) .3933.0565| 3.1753+.4566| 1.7907=.2574 
Shit, all, WOW scaooc 51 .7878+.0526| .3526+.0235) 2.0390+.1362| .3935+.0263) .3355+.0224| 2.8055+.1874| 1.5845+.1058 
Sin., all, 1908...... 598 .7346+ .0143) .4081+.0079) 2.4321+.0474| .3923+.0076) .3634+.0070} 3.0925+.0603) 1.7940+.0350 
Dex. ally 1908... <7 28 -8736+.0787) .4578+.0412| 2.2588+.2035| .4705+.0424| .3599+.0324) 2.7930.2517| 1.6241+.1464 
Sik, All, oosoc0cc0e 649 .7407+.0139| .4061+.0076) 2.4239+.0454| .4027+.0076) .3783+.0071| 3.0678+.0565| 1.8246+.0342 
OS UE 2 a 2) a a oe 
Comparing the plain and banded groups with one another, it appears that the 
relations of one annual series are reversed in the other. ‘The unbanded shells are 
collectively smaller than the others in the 1907 lot, but in the richer collection from 
the higher level they are larger, in both the sinistral and dextral groups. 
The pillar-tooth has been treated statistically in this colony and the figures are 
given in table 45. ‘The shells devoid of a tooth constitute a class with index 1; 
those with a “trace” make up the group with index 2, and so forth. ‘The data dis- 
close well-marked differences between the plain and banded shells of the dextral 
section, but otherwise the comparable series seem to be essentially alike in this 
character. 
The statistics of fecundity (table 46) refer to the 1908 series, and low degrees 
of productivity are indicated exactly as in the case of the 1909 series from Punaruu. 
All of the specimens obtained in the valley during 1907 were brought back alive 
for laboratory study, and hence their records are not available. 
Owing to the remarkably low productivity of the large 1908.collection, few data 
are at hand for the determination of the genetic relationships between the two 
