THE FRUIT: INDEHISCENT FRUITS 



207 



sunflower fruit, wheat fruit, corn fruit, grass fruit, etc., or oat 

 fruit and barley fruit. In the latter " seeds " not only are the seed 

 coats united with the pericarp, but this is firmly enclosed within 

 the palets of the flower. 



329. The schizocarp is a dry fruit consisting of several united carpels 

 (compound pistil) which splits at maturity in such a way that the carpels 

 separate from each other but do not themselves dehisce and free the seed, 

 as in the carrot family, mallow family. 



330. Nuts. 1. The acorn. The acorn fruit consists of the 

 acorn and the "cup" at the base in which the acorn sits. The 



FiR. 159. 

 Fruit of corn, husks spread to show ear. 



cup is supposed to be composed of a crown of numerous small 

 leaves (involucre) at the base of the pistillate flower, which be- 

 come united into a hard cup-shaped body. When the acorn 

 is ripe it easily separates from the cup, but the hard pericarp 

 forming the "shell" of the acorn remains closed. (Frost may 

 cause it to crack, but very often the pericarp is split open at the 

 smaller end by the wedge-like pressure exerted by the emerging 

 root during germination.) 



2. The hazelnut, chestnut, and beechnut. In these fruits 



