54 VARIATION, DISTRIBUTION, AND EVOLUTION OF THE GENUS PARTULA. 
outlined in this section; perhaps the solution can be obtained only by a repeated 
survey after the lapse of some years. 
EMBRYONIC MATERIAL. 
According to the orthodox mode of the genus, radiolata is ovoviviparous. Full 
growth is attained and the flaring lip of the shell is well formed before reproductive 
ability is manifested. The capsules in which the fertilized eggs are inclosed are 
oval, from 3.5 to 4 mm. in length; when several are present in the brood-pouch 
at one time, they are so crowded as to become somewhat cask-shaped, with flat 
contact-surfaces. The walls of these capsules are never impregnated with calcareous 
material, as in the majority of the Society Island species. The embryonic snail gains 
a shell approximately 3.5 mm. in length before it emerges to lead its independent life. 
TABLE 21.—Partula radiolata, Guam. Statistics of fecundity. 


: Date 
Locality. (1920). 
Taragves cies Saies Aural fst. 
Lolote . egg Ace July 7 
Batrigarda.; eae. css h July aos. ne ee 
Wkudw. ci oss. ee en ei July 2 
Dededo... Panera July.12. Sans 
DAUCIOw «tre erayeie ers ee xe s Walyracce css os 
Tumon to Agafia...... MATA src ce 
Anivuacey ys. eee Augais?..o9.s 
Cemetery .nac ane ae ANG 8. Sours 
Presidio, outer........ Aug. 15, 16, 25. 
Vioriowel.- oe ce or. TOly 2a. cn. os 
Wiig uppetgere ees ce July 2345, Seats 
Pago IRIVEN, 5 <u saan July 2 
Pago, north Kasse yulydl2 Joya 
LLOnGhee. cons eons eas Tune SO. enn 
? June’ 293. 60. 
Ordots wn eid: se ee Pee Ai, 
; JUly LBs de =<: 
Macajna;.. .ccereeers Agatti ee 
7 Vuly Goes aes 
Monte. ci cask easton Joly 4050.0. 
Cabras) east..4 56 = see Atigr ize. 
Cabras, west? :¢ 2. <n. Aug, 92.40. 
OFOtes cent reece ee JWysOl reece 
ASAE cn aty Aen ts eile ol eye ein oe 
Salifanss Ge. che Poe Ae 22305 &e 
Umatac Salonga...... SulyetSs he 
Umataé Paiom... .. ..). July 14-325. 
Umatac Madog......, July 14, 15 
Merizo).cagnana ewe 3 PULLS nk, Gite ga ee he 
Inarajans. 99s masters ae Auer 2Qees. : 
SUMIMALY ss. ona eR EEN, Mee 
Records 

























Gravid. 
No. Per 
cent. 
56 | 90.32 
2 | [100] 
20 | 86.95 
3 | 75.00 
S24 San 
55 | 88.71 
13 | 76.47 
32 | 86.48 
3 | [100] 
20 | 86.95 
183 | 89.70 
26 | 92.86 
14 | 73.67 
46 | 90.19 
20 | 80.00 
oleh Gai hee id 
28 | 96.55 
20 | 95.84 
94 | 86.24 
53 | 76.81 
121 | 93.07 
1 {100} 
11 | 84.61 
56 | 87.50 
54 | 87.09 
121 | 84.03 
‘71 | 85.54 
32 | 69.56 
1,313) 1° 86715 














Embryonic contents. 












Eggs. | Young.| Total. 
83 76 159 
5 4 9 
37 20 57 
6 6 12 
277 143 420 
130 78 208 
on 15 47 
88 49 137 
9 6 15 
64 36 100 
551 282 833 
79 38 117 
40 12 52 
134 59 193 
48 26 74 
76 34 110 
89 60 149 
40 25 65 









268 179 447 
2 1 3 
30 18 48 
187 91 278 
166 93 259 
221 104 325 






3,502 | 1,909 | 5,411 














Average for gravid. 
Eggs. |Young. 
1.48 | 1.36 | 2.84 
2.50 | 2.00 | 4.50 
1.85 | 1.00 | 2.85 
2.00 | 2.00 | 4.00 
2.25 | 1.16 | 3.41 
2.36 | 1.42 | 3.78 
2.46 | 1.15 | 3.61 
2.75 | 1.53 | 4.28 
3.00 | 2.00 | 5.00 
3.20 | 1.80 | 5.00 
3.01 | 1.54) 4.55 
3.04 | 1.46 | 4.50 
2.85 | 0.85 | 3.71 
2.91 | 1.28 | 4.20 
2.40 | 1.30 | 3.70 
2.17 | 0.97 | 3.14 
3.18 | 2.14 | 5.32 
2.00 | 1.25 | 3.25 
2.62 | 1.33 | 3.95 
3.24 | 1.72 | 4.96 
2.21 | 1.48 | 3.69 
2.00 | 1.00 | 3.00 
2.73 | 1.63 | 4.36 
3.34 | 0.62 | 3.96 
3.07 | 1.72 | 4.80 
3.07 | 1.661 4,73 
3.11 1.46 | 4.57 


The statistics of fecundity are given 1m extenso in table 21. Asonly afew adults 
were unavailable, the total number of records, 1,524, is satisfactorily high and fully 
