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It is interesting to notice the uniform structure of the inflorescence, always cymose,
but more or less modified into monochasia. Furthermore the constant presence of at
least one of the two prophylla; in Montiastrum there is but one; in Naiocrene both are
developed, but of very minute size; in Alsinastrum both are present, but of very
unequal size; finally in Limnia and Euclaytonia both are of the same size, and large. In
regard to the stem above ground this may be leafy, or destitute of leaves except the
prophylla. When only one internode is developed as in Euclaytonia and Limnia the
prophylla are the only leaves of the stem, the foliage proper being borne on the
extremely short central shoot; in these two sections the ramification of the shoot is
monopodial, the flower-bearing stems being developed from the axils of these leaves. A like
monopodium exists in Naiocrene, even though the flower-bearing stems consist of many
internodes with alternate, green leaves. In Alsinastrum, on the other hand, the leafy
stem is terminated by an inflorescence, and the leaves are opposite. Finally in
Mantiastrum the primary shoot is leafy from base to apex, but is not a monopodium.
The method of vegetative reproduction, also, deserves notice; bulblets sessile in the
axils of the cauline leaves we have seen in Naiocrene; bulbiferous, subterranean stolons
occur in Alsinastrum; stolons, subterranean, but not bulbiferous, occur, also, in
Alsinastrum, furthermore in Limnia, but only in a certain form of Cl. Sibirica; finally in Cl.
sarmentosa stolons above ground are well represented, and from these leafy rosettes
become developed. In the large-rooted species of Euclaytonia the monopodial shoot
winters over with a rosette of leaves in the axils of which the young inflorescences are
hidden until the coming of the spring; in Cl. Virginica and its nearest allies with a
globular, tuberous root, no leaves are visible during the winter, these being kept in the
ground together with the young inflorescences, which appear before the leaves. Nearly
all the species of the section Limnia are annual, but we have seen that Cl. asarifolia
is perennial, and that Cl. Sibirica, though typically an annual, does occur as a perennial
under favorable conditions. All the species of Montiastrum are annual. In regard to
the root-system we have seen the enormous development of the primary root in Cl.
megorrhiza, partly also in the other members of Euclaytonia. But in the other species the
primary root is slender, and does not persist for more than one season except in Cl.
Sibirica when perennial, and in Cl. parvifolia, where it, however, becomes replaced by
secondary roots. Secondary roots occur, also, in Alsinastrum, developed from the
internodes of the bulb, and sometimes also from the nodes of the slender stolons: in Cl.
sarmentosa such roots were noticed upon the stolons, beside at the base of the leafy rosette;
finally in Cl. Australasica the stems root freely at the nodes.
If we now compare the geographical distribution of these spedes of Claytonia, we
notice the occurrence of the large-rooted Cl. tuberosa and Cl. arctica in Siberia, of Cl.
sarmentosa, Cl. asarifolia and Cl. Sibirica on the islands of Bering Sea, from where they
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