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PLANTS AND MAN 



of these the pod is the only type which is of food importance. A 

 pod splits open at maturity along sutures which extend longi- 

 tudinally on either side of the fruit. In some cases the pod itself is 

 fleshy and eaten with the seeds, as in the string bean. Pod fruits 

 are typical of the legumes (Chapter 10). 



All of the preceding are sometimes known as simple fruits 

 because they develop from the single pistil of the flower. In 



B D 



Fig. 101. — Dry fruits include achenes, such as that of buckwheat (A); the 

 caryopsis, such as that of corn (B); nuts (acorn, D); and pods (pea, C). 



AGGREGATE fruits morc than one pistil is involved in fruit forma- 

 tion, so that after fertilization has taken place the ovary of each 

 pistil develops into a small fruit side by side with those of other 

 ovaries of the flower, on a common receptacle. Raspberries and 

 blackberries are such fruits. In other fruits, the calyx or the 

 receptacle aids the ovary in fruit formation; these are known as 

 ACCESSORY fruits, typical of apples, pears, strawberries and figs. 

 The most important of the dry fruits, from the human food 

 aspect, is the caryopsis of the cereal grasses. Like other members 

 of the Grass Family, the cereals have long tapering parallel- 



