214 Observation of tlic Origin of Varieties. 
to whether the mutants are immediately constant from 
seed. An almost insurmountable obstacle in the way of 
providing an answer to this question is the low fertility, 
or rather the almost complete sterility, of the peloric 
flowers. Practically no results can be obtained with 
self-pollination, and when artificially fertilized with one 
another's pollen the majority of the flowers set no seed. 
I have pollinated thousands of flowers in the course of 
several years, only to obtain a little over one hundred 
fertile seeds. Under these circumstances it is obviously 
difficult to avoid mistakes ; stray pollen grains may happen 
to reach the stigma from distant groups of normal plants, 
by the agency of insects, or in the operation of artificial 
pollination. 1 These circumstances evidently tend to in- 
validate the conclusion in cases in which the abnormality 
would seem to be incompletely inherited. 
Only three of the wholly peloric plants of 1896 set 
seed in that year. From this seed only 8 plants were 
raised ; five of them had one-spurred flowers and 3 were 
wholly peloric. I kept the peloric plants of 1896 through 
the winter, and took much trouble in 1897 in the attempt 
to fertilize their flowers. Every other day I pollinated 
all the open flowers with pollen from two other seed- 
parents. I obtained a very small quantity of seed most 
of which was empty (0.2 cc). About 100 seeds ger- 
minated, but some of the young plants were so weak 
that they soon died. 79 plants flowered most of which 
were very vigorous and branched freely ; 75 were wholly 
peloric, and 4 normal, the latter being removed as soon 
as possible. The former exhibited great variability in 
the structure of their flowers, but did not produce a 
single one-spurred corolla. During July and August they 
1 Such crosses give normal one-spurred individuals. 
