Elementary Work in Botany. 



coat of the solitary seed, while the lobes, clinging to animals 

 or flying with the wind, in due time bear away the ripe akene. 

 Composite flowers, then, furnishing the highest type of 

 capitate inflorescence, stand at the head of all. 



Bring for the next exercise all kinds of pods, akenes of 

 composite flowers, and green juicy fruits. 



EXERCISE 51. 



Fruit and Its Use to the Plant. Ovules fertilized by 

 pollen become seeds, and the ovary in which they grow and 



ripen develops into a pod, a bur, 

 a grain, a nut, an akene, or a 

 juicy fruit. All these seed bear- 

 ers are called fruits by botanists; 

 but only the last the juicy form 

 is known as fruit in the mar- 

 kets. Botanically considered a 

 fruit is the ripened ovary, or set 

 of ovaries, and all that directly 

 belongs to it. Seed vessels and 

 their attachments are fruits. In- 

 ferior ovaries become fruits in 

 which the calyx, as in musk- 

 melons, is a large part. Sometimes the receptacle encloses 

 the distinct akenes of a single flower, as in roses, or the 

 fruits of numerous flowers, as in figs. The juicy receptacle 

 of a strawberry bears many akenes, which, like those of a 

 fig, are commonly supposed to be seeds. Mulberries, osage 



Fig. 78. Two-carpel ed winged fruits 

 (samaras), a. Big-leaf maple (Acer ma- 

 crophyllum). b. Vine maple (A. circin- 

 atum). c. Califoruia box-elder. 



