EVENING PRIMROSE FAMILY ONAGRACEAE 
SEEDBOX 
Ludvigia alternifolia L. 
The Evening Primrose family is small and none of its 
members are economically important. The varied forms 
of the Evening Primrose of this family and the common 
garden Pea of the Pulse family 
inspired Hugo De Vries, present- 
day Dutch botanist, to use them 
as a basis of observations for his 
theory of mutation. 
The Seedbox grows 2-3 feet high 
in swamps and low wet woods from 
New Hampshire, southern Ontario 
and Michigan to Florida, 
Kansas and Texas. It is 
an erect, branching and 
nearly smooth perennial 
herb having tuberous or 
clustered roots. The 
leaves are lanceolate to 
linear-lanceolate and 
acute or pointed at both ends. 
The flowers appear from June to 
September singly in the axils of the upper 
leaves. The 4 green sepals persist on 
the fruit but the 4 yellow petals are 
likely to fall away if the plant is jarred. 
The 4 stamens are inserted on the calyx 
with the petals. The fruit is a cubical 
capsule about one-quarter inch long, 
which contains many seeds and is the source of the plant’s 
common name. It opens by a pore at the base of the short style. 
The Water Purslane, Ludvigia palustris (L.) Ell., is quite common 
in muddy ditches and swamps. It is very different from the Seedbox. 
Its oval leaves are opposite instead of alternate and its stems creep 
upon the mud or float, and root at the nodes. The calyx lobes are 
very short and when the plant grows in water there usually are no 
petals; if it grows on land there are often 4 small reddish petals. The 
capsule is 4-sided and about one-fourth of an inch long. This plant 
ranges throughout the United States and blooms from June to 
November. 
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