PARTULA CLARA. 71 
inhabited by clara. Hence marmorata is the most widely distributed variety of 
clara, and it is also the most recently dispersed color-form of this species. 
Although the distinctive coloration varies little throughout this wide range, 
the measurable shell characters are much diversified. ‘The single example from 
Apirimaue (fig. 25, plate 21) is the largest of the entire collection except one other 
shell of the variety incrassa from Aoua Valley. A specimen from Haavini, in 
Taiarapu, is very nearly the shortest of the whole series; the widest of all is likewise 
an example of marmorata, from Faarumai. The characters of the aperture are also 
extraordinarily variable; the relative width of a Maara specimen is even less than 
that of the narrowest angusta examples. Decortication sometimes occurs, as in the 
shells from Mahaena (fig. 26, plate 21). Of all color-types, marmorata is, in a word, 
by far the most variable in the structural characters of the shell. 
TaBLe 26.—Partula clara marmorata. Statistical description by valleys and by regions. 
Mean VALUE. 
Length aper- 
Shell. Aperture. ture= length 
Region. | No. [at eae OL eae ee ee : : shell, 
Length. Width. Proportions. Length. Width. Proportions. proportions. 
mm. mm. Decl. mm. mm. p. ct. Dp. ct. 
Maara... 3 | 15.8500 .2403) 8.5666 .0735) 53.8333+.3675| 8.3333 .0735| 5.8334+.0735) 65.5000+.8425) 55.8333+.3675 
Tenaire..| 17 | 15.6323+.1529| 8.8647+.0511| 56.6177+.3011| 9.0294 .0816| 6.4529+.0774| 71.3824 .3314| 57.5588+.2833 
Titaviri..| 12 15.1500 .1101) 8.9666+.0681| 59.0833 .2312| 9.0000+ .0626| 6.6000 .0539| 73.2500+.1967 59.4167 + .0960 
Vavii....| 19 | 15.4605+.1109 8.9105-.0501) 58.1843-£.2191| 9.1526 .0563) 6.5947=.0406| 71.7631-£.2291| 59.2360 .1492 
Vaiaaia..| 15 | 15.6300+.1115, 9.1400+.0512) 58.4334+.2808) 9.1800-+.0782| 6.7133.0516, 72.9000+.2970) 58.7000=£ .2638 
Tautira..| 10 | 15.1700.0653| 8.9800+.0639| 58.9000+.3721| 9.0600+.0533) 6.6000-+.0286| 73.0000=.3602| 59.8000: .2144 
Haavini..| 30 | 15.0700-.0900| 8.7733 .0409! 58.2334.2440| 8.8267 +.0452! 6.4667=.0351| 72.7666-.1957| 58.8333.1631 
Paraura..| 19 | 15.4289+.0836) 8.7421+.0631) 56.6579 .2669| 8.9421+.0607| 6.4579 .0517 71.8157 .2410) 57.9736: .2719 
Southern.| 33 | 15.5318=.1036| 8.8819+.0402| 57.1364 .2754) 9.0213+.0510 6.4394 .0515) 71.2879 .1147) 58.0152 .2086 
Taiarapu.| 78 | 15.3000+.0536) 8.9256+.0260| 58.2820 .1359| 9.0153 .0302) 6.5615+.0214) 72.4872+.1318) 58.9871 .1037 
Eastern..| 28 | 15.4460+.1148) 8.8000+=.0572| 56.9286+.2819| 9.0142+.0655) 6.4928+.0465) 71.7500 .1791| 58.3571 .2378 
All.......| 139 | 15.3776 .0456, 8.8914 .0208| 57.7374 .1201| 9.0165 .0247| 6.5187+.0198| 72.0540+.1216| 58.6295 -+.0930 
STANDARD DEVIATION. 
Maara... 3 | 0.6164.1697| 0.1885+.0519| 0.9428+=.2596) 0.1885+.0519) 0.1885+.0519) 2.1613=.5952) 0.9428 .2596 
Menaire..| 17 9344+ .1081| .3123+.0361) 1.8406+.2130| .4991+.0577| .4729+.0547| 2.0258+.2344| 1.7316+.2003 
Titaviri..) 12 .5656+.0779| .3496+.0481) 1.1873 .1635) .3214+.0442) .2768+.0381) 1.0103+.1391 -4930 = .0679 
Vavii....| 19 .7166+.0784| .3242+.0355) 1.4161+.1549) .3640+.0398) .2625+.0287) 1.4811+.1620 -9647 = .1055 
Vaiaaia..| 15 .6403+.0788| .2939=.0362| 1.6117+.1984| .4488+.0552) .2963+.0365) 1.7048+.2099) 1.5143+.1864 
Tautira..| 10 .3059+=.0461| .2993+.0451) 1.7435+=.2629| .2497+.0376| .1341+.0202) 1.6881 .2546) 1.0049+.1515 
Haavini..| 30 .7311+.0636| .3326+.0289| 1.9821+.1724| .3669+.0319| .2849+.0248) 1.5902+.1383) 1.3249 .1153 
Paraura..| 19 -5405+=.0591) .4082+.0446| 1.7242+.1886) .3924+.0429) .3345+.0366| 1.5577+.1704| 1.7579+.1923 
Southern.| 33 -8829+ .0733) .3424+.0284) 2.3460+.1947| .4346+.0361) .4389+.0364, .9772+.0811) 1.7773+.1475 
Taiarapu.| 78 .7033+ .0379| .3410+.0184) 1.7842+.0963) .3969+.0213) .2816+.0152) 1.7283+.0933| 1.3469+.0727 
Eastern. .| 28 9007+ .0811) .4488+.0404) 2.2108=.1992) .5139+.0463) .3644+.0328) 1.4047+.1266| 1.8654+.1681 
LN, So oec 139 .7978+ .0323| .3645+.0148) 2.1003=.0851) .4310+.1075) .3459+.0140) 2.1261+=.0861| 1.6264+.0659 
The abrupt change observed in passing from Vaihiria to Maara—from the 
range of prima to the territory of marmorata—is emphasized by the almost unique 
conditions of the Maara shells (table 26). Only 3 specimens were taken in this 
small valley, but they are strikingly consistent in their short, narrow, and relatively 
