286 A TEXT-BOOK OF BOTANY 



known representatives of the family are clematis, anemone, 

 hepatica, marsh marigold, and peony (Fig. 207); and also 

 the spurred larkspurs 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, etc. 



Nearly related to the buttercups is a peculiar family, 

 containing several well-known plants, and known as the 

 Mustard Family (Crucifercc). 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, 

 etc. 



165. Roses. This family (Rosacece) 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) BERRIES. It so happens that none of these are 

 true berries, but their real nature has been explained ( 143). 



Strawberries are so hardy that they may be grown in 

 almost any part of America, from Alaska to Florida (Fig. 

 234). The common cultivated varieties have been derived 



