number of cases as compared with its prevalence in the adult series. 
PARTULA OTAHEITANA. 
255 
Among the young (table 202) the banded pattern is exhibited in a very small 
question the distinctive bands develop only after the birth of the young snails. 
Series. 
Unbanded, sin.. 
TaBLe 201.—Partula otaheitana sinistralts. 
Length. 
mm. 
16.8992 + .0365 
Shell. 
Width. 
mm. 
Mean VALUE. 
Proportions. 
p. ct. 
9.5749 + .0199) 56.5872+ .1080 
Length. 
mm. 
8.7913 + .0208 
Aperture. 
Temarua Valley. 
Without 
Width. 
mm. 
6.7287 + .0168 
Proportions. 
p. ct. 
76.5205 .1241 
Length aper- 
ture + length 
shell, propor- 
tions. 
Pp. Ct. 
51.8949 + .0797 
Tooth, index. 
3.1224+ .0294 
cestata, sin..... 364] 16.8228 .0254| 9.5587+.0135) 56.7582+.0772) 8.7247 .0135| 6.6874 .0114| 76.5467 =.0865) 51.7720+.0584) 3.0301+.0183 
ANU, Gtioooooccs 559] 16.8495=+.0207| 9.5644 .0112) 56.6986 .0629) 8.7480 .0114| 6.7018 .0095| 76.5376 .0710) 51.8148=+ .0471| 3.0624+.0158 
Specimen 1, dex. 1) 16.55 9.90 60.5 8.30 6.70 79.5 50.5 3s 
Specimen2, dex. 1} 18.95 10.70 56.5 9.90 7.30 73.5 52.5 4. 
STANDARD DEVIATION. 
Unbanded, sin..! 195) 0.7561+.0258) 0.4130+.0141| 2.2366+.0764) 0.4307 .0147| 0.3477+.0119) 2.5699+.0877| 1.6495+.0564; 0.6105 + .0208 
cestata, sin..... 364 .7181=+.0179 .3834=+ .0095} 2.1849=.0546) .3828=.0095| .3233+.0081| 2.4473+.0611! 1.6509+.0413} .5199+.0129 
ING Sih eeeanoree 58) 2.2046 .0445) .4014+.0081| .3327+.0067| 2.4908=.0502) 1.6515 .0333) .5550+.0112 
7257+. | -RST= 0146 -3940 + .0079 
Tas iE 202.—Partula otaheitana sinistralis. Temarua Valley. 
FECUNDITY. HEREDITY OF PATTERN. 
Total 
contents. 
No. of | No. of 
eggs. | young, 
Young, 
cestata. 
Young, 
unbanded. 
Average | Average 
for gravid.} for all. 
Per cent 
gravid. 
No. of 
gravid. Total. 
Series. Records. 
94 
182 
273 90 
508 
179 
326 
94 
182 
161 
286 
142 
245 
Unbanded, sin... 
cestata, sin....... 
All, sin 447 387 505 276 276 
Varpoo, TEARATAPU, AND OpiriIROoA VALLEYS. 
The western boundary of Temarua Valley is the precipitous face of the high 
mountain sector that intervenes between Temarua and Orofere valleys (plates 6d and 
13). The ridge ends west of the former in dry boundaries without trees along their 
seaward faces, but passing westward, the slope recedes and obtains a degree of mois- 
ture that allows a growth of small forest (plate 16a). Vaipoo Valley is little more 
than a shallow depression of the coastward slopes; its stream is very small, excepting 
after a copious rainfall. “Tearatapu is about half a mile to the west of Vaipoo and 
partakes of the same character, although it is deeper and it extends higher up on the 
mountain side. Opiriroa is still deeper and longer in radial extent, and its valley 
bottom is more like that of an element like Teohu. 
A few snails were taken in Vaipoo and Tearatapu in the course of a close study 
of the area of vegetation along the ends of the mountain ridges, prosecuted mainly 
for the purpose of determining whether the habitable areas of radial valleys were 
connected between their mouths; this was found to be the case. 
