202 PHARMACEUTICAL BOTANY 



THE FRUIT 



The fruit consists of the matured pistil (carpel or carpels) and 

 contents, or ovarian portion thereof, but may include other organs 

 of the flower which frequently are adnate to and ripen with it. 

 Thus in the Apples, Pears and Quinces, the receptacle becomes thick 

 and succulent, surrounds the carpels during the ripening process and 

 forms the edible portion of these fruits. In Dandelion, Arnica, and 

 many other members of the Composite, the modified calyx or pappus 

 adheres to the ovary during its maturation into the fruit and renders 

 the fruit buoyant. In Gaultheria the calyx becomes fleshy, sur- 

 rounds the ovary, reddens, and forms the edible part of the fruit. In 

 Physalis the calyx enlarges considerably and encloses the ovary in an 

 inflated colored bladder. Involucres frequently persist around and 

 mature with the fruits. These may be membranous as in Anthemis, 

 Matricaria and other Composite, leathery and prickly as in the Chest- 

 nuts, scaly woody cups (cupules) as in the Oaks, or foliaceous cups as 

 in the Filberts. Occasionally, as in the Fig, Osage Orange, Mul- 

 berry, etc., the fruit may consist of the ripened flower cluster or 

 inflorescence. 



FRUIT STRUCTURE 



The Pericarp, or seed vessel, is the ripened wall of the ovary, and in 

 general the structure of the fruit wall resembles that of the ovary, but 

 undergoes numerous modifications in the course of development. 



The number of cells of the ovary may increase or decrease, the 

 external surface may change from soft and hairy in the flower to hard, 

 and become covered with sharp, stiff prickles, as in the Datura 

 Stramonium or Jamestown weed. Transformations in consistence 

 may take place and the texture of the wall of the ovary may become 

 hard and bony as in the Filbert, leathery, as the rind of the Orange, 

 or assume the forms seen in the Gourd, Peach, Grape, etc. 



Frequently the pericarp consists for the most part of other ele- 

 ments than the ripened ovarian wall and is then termed a pseudocarp 

 or anthocarp. The pericarp consists of three layers of different tex- 

 ture, viz.: epicarp, mesocarp and endocarp. The epicarp is the 

 outer layer. The mesocarp the middle, and the endocarp the inner 



