PARTULA OTAHEITANA. 195 
All of the shells secured were unbanded, and dark brown, lighter rufous brown, 
or yellowish brown in color (plate 29, figs. 1 to 3). The sinistral shells (plate 29, figs. 
4 and 5) in some cases possess a tinted margin of the aperture, but the tinge never 
approaches the pink color of the red rubescens specimens. 
Passing now to the statistical analysis (table 128) we may unite all of the shells 
into one series for comparison with those of other valleys, and we may also compare 
the fuller series from the middle and upper parts of the inhabited area. In the 
latter case it is found that the former are longer and slenderer than the upland col- 
lection; the same may be said of their apertures. Hence the variety is not uniform 
throughout its area. Perhaps the larger size of the outward snails is due to a more 
searching elimination of the smaller and weaker individuals, as suggested by the 
facts in the case of rubescens. 
The fecundity of the snails (table 129) is high in all three series, which is sur- 
prising in view of the different times and seasons of collection. 
TasLe 129.—Partula otaheitana affinis. Papenoo Valley. 
FECUNDITY. HeErepIty. 
R d No. of | Percent} No. of | No. of | Total Average | Average Young,| Young, Total 
ecores: gravid.| gravid. | eggs. | young. |contents.| for gravid. | for all. dextral.| sinistral. ‘ 
DexrlOO0Steemiiecriiers 55 45 81.8 48 69 117 2.60 2 WP) Adults: 
1909 Fees 81 71 87.6 129 63 192 2.70 2B Dex..| 133 0 133 
= =| Gingd! © 6 8 11 
Dex., all years........ 138 117 84.7 178 133 311 2.65 2.25 |_—_______—_ 
Total 136 8 144 
Sin., 1908, 1909....... 7 7 100 13 11 24 3.43 3.43 | 
Heredity (table 129) of the dextral character is invariable in the case of 133 
young produced by such parents, but the sinistral adults bore reversed young in 
only 3 out of 11 instances. The data make it certain that the two form-classes are 
not genetically distinct; it would seem that the majority of reversed individuals 
arise by mutation from directly coiled parents. 
Partula otaheitana affinis erythrea subvar. nov.—Farapa Valley. 
Although the mouth of Farapa Valley is little more than a mile beyond that of 
Papenoo, the colony of the former area differs remarkably and presents features of 
the association as a whole that are truly distinctive. All the shells exhibit the 
fundamental characters that set this variety apart from other primary divisions, 
and many specimens are exact counterparts of the kinds described heretofore, but 
the secondary features of the majority are virtually unique; specifically, the plain 
examples exhibit a considerable amount of red that overshades the yellowish ground- 
color, while reddish bands encircle the whorls in a well-marked subdivision of the 
striped class, so that the distinctive taxonomic term erythrea is given to the colony 
as a whole for use as a brief designation. Nearly 600 adults and 30 adolescents 
were taken, while the embryonic young dissected out of the former amount to 506, 
all of which afford an ample representative series of the unique association. They 
are dextral without a single exception. 
