Here, however, the cestata group 1s the largest. 
PARTULA OTAHEITANA. 
Maara VALLEY. 
235 
The general composition of the sinistrorsa colony from Maara is like that of 
Tenaire, inasmuch as all three color-classes are represented in each mode of coil. 
their illustration unnecessary. 
On statistical examination (table 180) the sinistral cestata and phea groups prove 
to be shorter and stouter than their dextral correspondents—relations which are the 
exact opposites of what was found in Tenaire. 
consistently stouter than the dextral division, although in some cases, such as the 
proportions of the aperture, the figures are similar. 
Shell. Aperture. Length aper- 
Series. No. Seta Tooth, index. 
Length. Width. Proportions. Length. Width. Proportions. tions. 
mm. mm. p. ct. mm, mm. Do Be p. ct. 
apex, sin..... 7 | 17.5786+.1146| 10.3000 .0982) 58.5000 .5098) 8.9000+.1020) 7.0429+.1080) 78.6428 .8111) 50.6428=.3712| 1.1428+.0892 
cestata, sin...| 76 | 18.0461 .0651) 10.2921+.0327) 56.9210+.1789| 9.1158+.0384; 7.0474 .0270| 77.3684 .2319| 50.6052+.1600) 1.0658+.0192 
phea, Sintrrsris 49 | 17.9602 .0720| 10.3367 + .0478| 57.2347 = .2301) 9.1735 .0443) 7.1163+.0360| 77.4592 .2571| 50.8877 +.1638| 1.1600 -0398 
All, sin...... 132 | 18.0045+.0473| 10.3091 .0264| 57.1212 .1381| 9.1276+.0284) 7.0727+.0214| 77.4697 .1704) 50.7121=.1124| 1.1052+.0193 
apex, dex.... 4 | 18.1375+=.2723) 9.9000 .0477| 54.7500 .9868) 8.9500+.0559| 7.0000+.1216 77.6250 * 1.3630) 51.0000 .7727| 1.0000+.0 
cestata, dex...) 36 | 18.0167+.0909) 9.9112+.0299) 55.0278+.2874) 9.0889=+ .0468) 6.9167+.0376) 75.8055+ .3076) 50.5000+.2385| 1.1666 .0265 
phea, dex....| 29 | 18.1638+.1064| 10.0035+.0601| 55.0173+.2803) 9.1690+.0618) 6.9207 .0457| 75.3621 .3628) 50.4655=.2547) 1.1724 .0473 
INU, GIEo c006 69 | 18.0848 .0673) 9.9493+ .0353) 54.9203 .1986) 9.1145+.0361| 6.9232+.0284) 75.7319 .2387) 50.5145+.1701| 1.1571+.0293 
STANDARD DEVIATION. 
apex, sin..... 7 | 0.4495=.0810) 0.3854+.0684| 2.0000+.3605| 0.4000+.0711) 0.4238+.0754; 3.1816+ .5735| 1.4562+.2625) 0.3499 .0621 
cestata, sin...| 76 -8419+ .0460 4223+ .0231| 2.3128+.1265) .4971+.0261} .3491+.0181) 2.9971+ .1640) 2.0684+.1131| .2479=+=.0126 
phea, sin..... 49 7475+ .0499| .4959+.0338) 2.3885+.1627| .4601+.0313) .3743+.0244) 2.6683+ .1818) 1.7001+.1158) .4176+.0271 
ANIL GtMeo5050 132 -8052 = .0334, .4498+.0187) 2.3533+.0976) .4833+.0201) .3649+.0151) 2.9023+ .1205) 1.9149+.0795| .3305+.0126 
apex, dex.... 4 -8076+.1925| .1414+.0337| 2.9262+.6968) .1658+.0395) .3605+.0860) 4.0415+ .9638) 2.2913+.5454| .0 
cestata, dex..| 36 .8092= .0633| .2665+.0211} 2.5569+.2032| .4162+.0331| .3346+.0266) 2.7368 .2175| 2.1213+.1676) .2357+.0177 
phea,dex....| 29 -8500=.0752) .4804+.0425) 2.2379+.1982) .4935+.0437| .3652+.0323) 2.89714 .2565| 2.0339+.1801| .3778+.0334 
All), dex. .... 69 -8291+.0476) .4352+.0249| 2.4459+.1404| .4443+.0255| .3498+.0201) 2.93974 .1688) 2.0955+.1203| .3639+.0197 
| 
TasLe 180.—Partula otaheitana sinistrorsa. 
Mean VALUE. 
The shells are so typical as to render 
The reversed group as a whole is 
Maara Valley. 
the direction of coil is something that can be determined with certainty. 
Considerable variation in fecundity is displayed (table 181), but it remains an 
open question whether differential fertility actually exists. 
As before, the data of heredity must be treated with reserve in the case of color; 
In pre- 
senting the facts (table 182) we may include a number of very small snails (“egg- 
young’’) which were sufficiently advanced to display their direction of spirality but 
not their definitive colors. A slight excess of the dextral type appears in the embry- 
onic population (table 182). Combining the groups of apex and phza adults a slight 
decrease of cestata among the young is observed, but this is probably due to a later 
appearance of the bands in certain cases. 
