260 VARIATION, DISTRIBUTION, AND EVOLUTION OF THE GENUS PARTULA. 
and 37 are aberrant in the colors of the subsutural region. When the two color- 
classes are compared statistically (table 208) the remarkable fact appears that their 
relations in the case of sinistral shells are just the opposite of those displayed by the 
two dextral color-classes, so far as the differences in absolute measures are con- 
cerned. In both modes of coil, however, the cestata shells are broader, and their 
apertures are relatively wider. The dextral and sinistral groups differ from one 
another in interesting ways. In all sections the columellar tooth is very poorly 
developed. 
TasLe 209.—Partula otaheitana sinistralis. Maruia Valley. Fecundity. 
No. of | Per cent | No. of | No. of Total Average Average 
Series: Records: gravid.| gravid. | eggs. | young. | contents. | for gravid. for all. 
iPlainwisin sere 42 36 85.7 53 44 97 2.69 2.31 
Banded, sin.......- 61 46 75.4 75 44 119 2.58 1.95 
SAMI; siti. jspensnocarerene ie 103 82 79.6 128 88 216 2.63 2.09 
Banded, dex....... 1 1 1 2 3 3.00 3.00 
TaBLe 210.—Partula otaheitana sinistralis. Maruia Valley. 
Fuiu Data oF HerRepItTy. 
Young, sin. Young, dex. 
Plain. | Banded.| Plain. | Banded. 
Adults: 
Plain, sin 
Banded, sin 
Plain, dex 
Banded, dex 
Summary. Herepiry oF Coit. 
HEREDITY OF PATTERN. 
SUMMARY. 
Banded young, 
sin. and dex. 
Plain young, 
sin. and dex. Total. 
Adults: Adults: 
Plain, sin. and dex.... 36 8 44 Son 
Banded, sin. and dex.. 20 26 Lil linaoad Dkealoty aiged'can 
PPotalacnrertercn rteterer 56 34 9 ON eeRotal eres 
Fecundity is high throughout the series (table 209). Only one record of a 
dextral snail is given, because the adults of this kind were kept alive for transport 
home; hence the table of heredity (table 210) is somewhat misleading on account 
of the lack of records from dextral adults. The positive results are (1) that sinistral 
parents of both color-types produce young of all four kinds; (2) that the plain young 
are fewer relatively in their generation than the unbanded adults in theirs; (3) 
that the group of sinistral young is relatively smaller, but this last result is not to 
be taken as final for the above-stated reason. 
