2S6 A TEXT-BOOK OF BOTANY 
known represcutatives of the family are clematis, anemone, 
hepatica, marsh marigold, and peony (Fig. 207); and also 
the spurred Jarkspurs and columbines. Closely related to 
this family are a number of smaller ones, that share its 
general characters, and that contain such familiar plants as 
May-apple, water-lilies, barberry, bloodroot, poppies, ete. 
Nearly related to the buttercups is a peculiar family, 
containing several well-known plants, and known as the 
Mustard Family (Cruciferw). The flowers are peculiar in 
having four sepals in two sets, four petals in one set, 
six unequal stamens (two short and four long), and one 
carpel whose ovary is divided by a “false partition,” 
giving to the pod (long or short) the appearance of being 
made up of two carpels (Fig. 281). Not only is the family 
to be recognized by this singular floral structure, but also 
by its more or less pungent taste, which reaches an extreme 
expression in commercial mustard, which is made by grind- 
ing to powder the seeds of certain species. Among the 
members of the family that are prized either for ornament 
or for use are stock, sweet alyssum, candytuft, wallflower, 
watercress, horseradish, mustard, cabbage, turnip, radish, 
ete. 
165. Roses.—This family (Rosacew) is one of the best- 
known and most useful families of the temperate regions. 
Many of the flowers have a structure that suggests that of 
the buttercups, but the family is so extremely varied in this 
respect that no general description can include them all. 
In addition to such beautiful ornamental forms as the roses, 
the family contains a remarkable collection of valuable 
fruits. These fruits may be considered under three heads: 
(1) Berrirs.—It so happens that none of these are 
true berries, but their real nature has been explained (§ 143). 
Strawberrics are so hardy that they may be grown in 
almost any part of America, from Alaska to Florida (Fig. 
234). The common cultivated varictics have been derived 
