ON SELF-STERILITY. 215 
vigorously, but so far, unfortunately, has not flowered. It is to be hoped 
that by its aid I shall succeed in rendering the European race a fertile 
one. 
How far the signification of the self-sterile physiological individual 
should be carried, I learn from a letter of my late friend Dr. Fritz Miller, 
at Blumenau, in Brazil, dated January 24, 1895, referring to my com- 
munication regarding the planting of the American Calamus. For some 
years a beautiful Amaryllis, which is plentiful in the gardens about 
Blumenau, and which morphologically constitutes the offspring by bulb 
propagation from a single imported individual, has been observed to be 
entirely sterile. In 1884 Fritz Miller found the species growing wild 
near the sea, and crossed with individuals from this source, the garden 
form became fertile. A still more striking example of self-sterility is 
seen in Hedychiwm coccineum. The morphological individuals of the 
species are quite sterile between themselves, although the pollen is 
normally developed, and the species, united either as male or female, 
forms hybrids with kindred species of the same genus. Some years since 
Fritz Muller received Hedychiwm coccineum from Buitenzorg, among 
other Zingiberacee, and crossed numerous flowers of the plants— 
which had certainly been introduced into Brazil more than a century 
before—with these Javanese individuals, but without any results. He 
concludes, therefore, ‘‘ that the individuals raised both in Brazil and in 
Java as decorative plants came from one and the same garden, into 
which a wild plant had originally been introduced.” 
Iam much encouraged in the hope that I may restore fertility to the 
Kuropean Calamus by the following, in many respects, instructive attempt 
with Trientalis europea. 
I am acquainted with three quite isolated stations of this plant in the 
woods round Greiz, isolated but very extended, and far from any others. 
These, together with other relics, may have existed (according to Aug. 
Schulz) since the fourth of the Ice periods which are to be distinguished 
in Thuringia.* In any case, these stations have been occupied from time 
immemorial; and it appears, moreover, that at the present stations 
all the plants spring from the same rhizome, and have only propagated 
themselves by means of the rhizome because they are self-sterile, and for 
more than twenty years I have sought in vain to find a single seed 
capsule. At .a distance of about four geographical miles Trientalis is 
found in quantity, and I brought examples from Struth at Niederpéllnitz 
in 1895 for observation in my garden, where they were fertile both with 
their own and with foreign pollen. In 1895 I planted four, and on 
March 29, 1897, some more examples from Struth among the self-sterile 
form in the Kriimmthal, near Greiz, where annually thousands of self- 
sterile examples flower, and marked the places. The result was as 
expected. Kven in 1895 I found not. only on the introduced plants, but 
also on several of the old indigenous form, well-developed seed capsules, 
which also came to maturity. In 1898 I found about fifty ripe seed- 
vessels. The rejuvenescence of the race, self-sterile for ages, had thus 
been successfully effected ; and the Calamus must, I think, also succeed. 
* « Grundziige einer Entwickelungsgeschichte der Pflanzenwelt Mitteleuropas seit 
Ausgang der Tertiarzeit,’’ Iena, G. Fischer, 1894. 
