56 VARIATION, DISTRIBUTION, AND EVOLUTION OF THE GENUS PARTULA. 
applicable unless newly formed capsules are actually pushed past older ones to a 
place in the series nearer to the birth-aperture, as the writer supposed was generally 
the case. A few true anachronisms have been observed in Tahitian species and in 
P. gibba of the Mariana Islands, but in the case of radiolata there are no germs at 
all within the capsules in question or else an unfertilized egg is present. The 
exceptional cases are recorded in table 22, in which the item nearest to the birth- 
aperture is given first and the others follow in the order of their formation. 
The number of embryos of all ages that are present in the brood-pouch ranges 
from none to 10; the full data are given in table 23 and require no comment. 
TABLE 23.—Partula radiolata, Guam. Recorded adults and their embryonic contents. 



Number of young. 
Totals. 
0 1 2 3 4 
Number of eggs: 
ues sdhanal eer teeter eave 211 28 9 
W cisssrettine cites Pre 64 62 $5 10 
PATO AP dei ey thi 71 115 176 25 2 
Sina kG ney sae eee 74 88 158 52 1 
Ais cpmiwe rani ORE 30 49 109 28 7 
5 git urate careers 12 20 30 17 4 
One clelia sarees in 5 3 4 3 
| RR Scacrocacyit es 1 
re Ann Oras 
Dis.nsg bie omedeee as 
1 i ae ae 1 
Totals.capeee er 468 366 541 135 14 
1524 records 
1909 young 
Embryonic contents. 
Summary. 
Number of adults—1,524...| 211 92 | 142 | 244 | 304 | 244 | 188 62 29 7 


A question of much interest is whether there is a well-defined breeding season 
which alternates with an interval when multiplication is suspended. In the 
monograph on the Tahitian species the reasons were given for the belief that the 
several valley colonies of such a species as P. otaheitana behave independently; 
specifically it was found that during a particular month the members of one associa- 
tion contained many eggs and young, while a colony in even a near-by valley would 
be almost barren, or at least would display a very low rate of productivity, and hence 
it seemed that each community possessed its own reproductive cycle without any 
discernible relation to seasonal changes. In radiolata, however, the contrary is 
the case, for the facts show that with the onset of hotter weather and of the heavier 
rains, the adult animals begin to produce a new generation of offspring. 
While the ultimate proof of this assertion would require the actual collection 
and dissection of representative series throughout a full annual period, yet the data 
of table 21 provide a clear demonstration of the point, despite the fact that the 
