THE ROSE FAMILY 363 



as in certain of the poppy family, but the ovary instead of 

 being one-celled is divided into two compartments by a 

 partition extending between the parietal placenta. When 

 ripe the carpels mostly separate from the placenta and from 

 this partition. Such a fruit is called a silique.^ The ovules 

 differ from any we have seen among the plants of the crow- 

 foot order in lacking a raphe and being curved to a somewhat 

 kidney-like form. When thus curved, ovules are described 

 as campylotropous.- 



The seeds are almost alwaj's exalbuminous and have the embrvo 

 commonly bent in ^'arious ways — a peouliaritj' expressed in the 

 formulas by GA- 



Note how closely similar are the formulas of Brassica, Nasturtium, 

 Raphanus, and Cruciferai given on pages 406, 407. 



As a definition of the family we have thus: — 



Mustard family: mostly herbs without milky or colored juice 

 or oil reservoirs, often of sharp taste though pleasant flavor; 

 ebracteate inflorescence; usually hypogynous flowers with all 

 the parts in whorls of two (with the apparent exception of the 

 four inner and longer stamens), the ovary divided into two cells 

 by a partition joining the parietal placentce; the fruit almost 

 always a silique with exalbuminous seeds having the embryo 

 variously bent. 



111. The poppy order (Papaverales or Rhoeadales) com- 

 prises a few families well represented b}^ the poppy and the 

 mustard families and agreeing in having mostly racemose 

 inflorescences of complete, hypogynous, regular or irregular 

 flowers with the sepals, petals, and stamens all distinct and 

 free, and a compound pistil ivith parietal placentce. It is 

 the union of the carpels by their edges which mainlj' dis- 

 tinguishes this from the cro'wfoot order. 



For comparison we have a tj'pical formula of the order on pages 

 408, 409. 



112. The rose family (Rosaceae) as illustrated by the 

 almond (Fig. 31, page 42), apple (Figs. 91 I, II, pages 86, 

 87), pear (Fig. 92, page 87), quince (Figs. 93 I, II, page 88), 



1 Si-lique' < L. siliqua, a pod; C i - . 



2 Cam-py-lot'ro-pous < Gr. kampytos, curved; (rope, a turn. E S. 



