104 VARIATION, DISTRIBUTION, AND EVOLUTION OF THE GENUS PARTULA. 
The statistical determinations (tables 50 and 51) show that the contrasted 
classes are not identical in the measurable and proportionate characters of the shells 
or in the degree to which the pillar tooth is developed. Fecundity (table 51) is 
low as in the other colonies of this species. Again the parents of any class (omitting 
the two specimens of Class I) produce their own kind (table 51), but they also bear 
different kinds of offspring as well. 
Tasie 50.—Partula nodosa. Aoua Valley. 
MEAN VALUE. 
Shell. Aperture. Length aper- 
ture + length 
Group. No. ehelltpronons 
Length. Width. Proportions. Length. Width. Proportions. tions. 
mm. mm. p. ct. mm. mm. p. ct. p. ct. 
Classe ltteer 2 | 14.7500+.1431| 9.1000+.0 61.5000 + .4769| 8.0000+ .0477| 6.5000+.0954) 80.5000 .4769) 54.5000+.0 
Glass) Iles eae 309 | 14.4034 .0263) 8.9078.0157| 61.7427 = .0820) 7.8817+=.0144| 6.3376+.0121) 80.2703 .0961) 54.5500+.0596 
Glasspllleer errr 23 | 14.3326 .0675| 8.9696+.0350| 62.5869 .1985| 7.9697 = .0394) 6.3870 .0267| 80.1956 + .3309| 55.4130 .1459 
(EGS IN so oc6 500 48 | 14.5938 .0607| 9.2000+ .0355} 62.9375 .1831) 8.0250+.0414) 6.4209 .0327| 79.8541 .2632| 54.9166 .1753 
iN Gasccuadogade 382 | 14.4249+ .0231| 8.9492+ .0141) 61.9424+.0750| 7.9058+.0131) 6.3519 .0108) 80.2146+.0872) 54.6544 .0545 
STANDARD DEyIATION. 
Classiemlinererrecr 2} 0.3000+.1012 0 | 1.0000+ .3372) 0.1000 .0337| 0.2000+.0674| 1.0000+=.3372 0 
CHEE Who ssoooc 309 .6862 + .0186) 0.4105+.0111) 2.1367+.0580) .3749=.0102) .3147+.0085) 2.5061.0679) 1.5548=.0421 
Classpilrae irra 233 4904+ .0477| .2544+.0247| 1.4421+.1403) .2866+.0278| .1938=+=.0189| 2.4035+.2340) 1.0597+.1032 
Chg IN oo00000 48 .6237+.0429) .3651+.0251) 1.8809+.1295} .4255+.0293) .3360+.0231) 2.7041+.1861| 1.8009+.1239 
YW ini ctomioscan 382 .6707 + .0163 A019 .0109 2.1708 .0530) .3795+.0093} .3126+.0076| 2.5242+.0617| 1.5769=.0385 
TasiE 51.—Partula nodosa. Aoua Valley. 
Tooru. HEREDITY. 
Fecunpity (390 Recorps). 
Large 
tooth. 
Young,) Young, 
plain. | banded, toee 
Group. 0 | Trace.| Tooth. 
Class I.| 0 0 2 (0) Gravid Seeeienere nee 103 Adults: 
Class II.} 3 4 314 0 321 Per cent gravid....| 34.1 Plain (Class IV)..] 12 5 
Class III.} 2 1 20 0 23 _———— Banded (Classes 
Class IV.| 0 2 48 0 1Be-eY grid an aeaouOG 137 IQ @yaXol IDOD) 4 oan 23 
SOROS 5 Be eaatels PRAT 
Average for gravid... Loo 
Average for all..... 0.5 
Partula nodosa intermedia var. nov.—Orofere Valley. 
In discussing the range of P. nodosa at an earlier point (p. 90) it was stated that 
no specimens of this species were obtained in 1907, but that a few were taken in 
1908 in Orofere Valley. In the former year the area of exploration extended to a 
point 3 miles from the coast and included both borders of the stream; in the latter 
year nodosa was discovered on the northern border of the river (on the side adjacent 
to Aoua Valley), 2 miles from the shore. Ten banded animals were secured on one 
occasion and 7 banded specimens togetherwith 1 plain shell on a second trip. There 
