PARTULA OTAHEITANA. DEB 
Fecundity (table 198) is low in the 1906 series, but fairly high in the small 
1907 series; the reasons have been pointed out earlier at several points. 
The assignment of embryonic young to color-classes equivalent to those of 
the adults is not possible throughout, because the unbanded young do not display 
the distinctive characters of the apex type until after they are born, judging by the 
adolescents studied. Grouping all of the plain individuals together (table 198), 
the numbers of cestata among the offspring are fewer than among the gravid adults, 
leading to the conclusion that the developemnt of stripes, like the appearance of 
the darkened spire in apex, is deferred. 
A single dextral banded shell was borne by a plain sinistral adult! On the 
basis of the adult and adolescent series, the colony would seem to be entirely devoid 
of the dextral character in its heritage; the value of the embryonic snails is nowhere 
clearer than in such a case as this. 
Paperiti VALLEY. 
Despite the close geographical relationship between Papeiti and its sister valley 
Temarua (a matter discussed earlier), the sznistralis colonies are intrinsically as 
different as though the two localities were entirely separate. 
TaBs_eE 199.—Partula otaheitana sinistralis. Papeiti Valley. 
Mean VALUE. 
Shell. Aperture. Length aper- 
Series. No.) Baie Tooth, index.} 
Length. Width. Proportions. Length. Width. Proportions. tions. 
mm. mm, p. ct. mm. mm. p. ct. p. ct. 
ADCKS Tessie es 8) 16.7375 .1515] 9.2500 .0782) 55.1250+.5324| 8.6250+.1142) 6.5000+.0337| 75.7500+.6281| 51.1250+.3759| 3.0000 .1192 
phea striata..... 142) 16.5479 .0438) 9.3268+ .0245| 56.3028+.1306| 8.5366+ .0256) 6.5366+ .0213) 76.5352+.1529) 51.4366 .0994) 2.8733 = .0328 
phea confluens...| 116) 16.7517 .0424| 9.4362+.0229) 56.3017+.1532! 8.6362+.0261| 6.5793+.0216] 76.2155=+.1836) 51.3103+.1194| 2.9483 .0375 
Unbanded classes} 266) 16.6425 .0326| 9.3722+.0168) 56.2664 .0982) 8.5827=+.0182) 6.5541 .0158 76.3722 .1162| §1.3722 += .0753) 2.9098 + .0243 
CEMA. sooadous 208) 16.7014 .0340) 9.2993 += .0202) 55.5096 .1054) 8.5240 .0189| 6.5240+.0172] 76.3076+.1330 50.9760+.0774| 2.8708 .0291 
PAN Peeiiehey ss egevsicettesess 474] 16.6684+ .0236) 9.3359 .0130} 55.9346+.0729) 8.5506 .0129) 6.5409 .0112] 76.3439 .0794) 51.1983 .0545) 2.8926+.0187 
STANDARD DEVIATION. 
| 
ADEK Merete veer 8} 0.6353+.1071) 0.3279=.0553| 2.2326+.3765) 0.4789 .0807| 0.1414 .0238) 2.6339+.4441| 1.5762=.2658| 0.5000+.0843 
phea striata..... 142 .7739+ .0310) .4328=.0173) 2.3081+=.0923) .4519+.0181) .3758=.0151) 2.7021+.1081) 1.7571+.0703) ,5797+.0232 
phea confluens...| 116 .7993+.0353} .3654.0162) 2.4468+.1083) .4165+.0184) .3453+.0153) 2.9326+.1298| 1.9069+.0844) .5995+.0265 
Se | he ee a a le ee Se on ee he 8 a—E—oo 
Unbanded classes} 266 .7879 = .0230| .4058=.0119| 2.3759+.0694| .4405+.0129| .3813+=.0112) 2.8108+.0822) 1.8206+.0532] .5876+.0172 
Cesta tarenrerieian 208 .7265+ .0240) .4315+=.0143) 2.2532+.0745| .4043+.0133) .3674+.0122| 2.8440+.0940) 1.6552+.0547| .6241+.0206 
AM c:6 co aie ee 474 .7622=.0167) .4194=.0092) 2.3535+.0515} .4159+.0091;} .3626+.0079| 2.5629+=.0561] 1.7609+.0385) .6044=.0132 
1The numbers are: cestata, 209; total, 475. 
The color-form apex is represented by 8 adults, or 1.7 per cent. The cestata 
shells differ from those of Teohu in having the bands sharply outlined (plate 32, 
figs. 14, 15); none of them is like the intermediate form of Teohu shown in plate 32, 
figure 5, although in some cases the sutural band fades out along the line of articu- 
lation of successive whorls (plate 32, fig. 15). The most notable feature of the 
whole colony is the division of the phea class into confluens (plate 32, figs. 12 and 13, 
