S. pratensis of Michigan Flora.

An Old World native, familiar as a naturalized weed, but apparently not collected in Michigan before 1865 (Berrien Co.). Common in all kinds of disturbed sites: roadsides, fields, shores, gravel pits, banks, and edges of forests; often on dry sites.

Silene latifolia is an example of a dioecious plant in which sex determination results from X and Y chromosomes, as in the human species. The calyces of staminate plants are 10-nerved; those of pistillate plants, 20-nerved (with alternate nerves stronger than the others). (In S. noctiflora, the calyx is 10-nerved and there are prominent white glabrous areas between the nerves, especially in fruit.)