THE FRUIT 401 



term, include parts derived from the style, the floral axis, 

 and even the calyx and the peduncle. A strict and uniform 

 application of the term is not easy. Where the pistil is 

 apocarpous the product of each carpel is entitled to be called 

 a fruit, and the collection must also be called a fruit, especially 

 in such cases as the strawberry, where it is set on a fleshy 

 axis ; such fruits may be distinguished as polycarpic. 

 Again, in some cases, what is commonly regarded as a fruit 

 is the product of a number of separate flowers, as in the 

 mulberry or fig. These may be called collective fruits. 

 Neither the statement that the fruit is the result of the 

 fertilisation of a carpel or syncarpous ovary, nor that it is 

 the result of fertilisation of a single flower, covers all the 

 common fruits ; and we must use the term rather broadly ; 

 this does not matter as long as we are aware of what exactly 

 is involved. 



The ovary enclosing the ovule, which develops into the 

 fruit enclosing the seed, is the distinctive feature of the 

 angiosperm. Biologically it may be regarded as affording 

 greater protection and superior nutrition to the ovule, as 

 well as greater protection, and the production of more 

 varied means of dispersal, for the seed. The commonest 

 change in the ovary, which usually denotes the setting of 

 seed, is swelling. The ovarial wall becomes the pericarp or 

 wall of the fruit. This may be leathery in texture, as in the 

 broom, or hard and stony, as in the hazel nut. Its middle 

 tissue or mesocarp may become fleshy, as in the tomato ; 

 and, in addition, its inner layer, the endocarp, may become 

 hard and stone-like, as in the plum. 



In epigynous flowers part of the floral axis forms the 

 outside of the ovarial wall, and is concerned in the wall of 

 the fruit. It is possible that this co-operation of the axis 

 in the formation of ovary and fruit wall is a more perfect 

 arrangement for nutrition and protection of the developing 

 seeds. In berries, such as the gooseberry, and drupes, such 

 as the walnut, the changes following fertilisation spread 

 to the floral axis. More striking are those cases, like the 

 strawberry, where the independent axis of a hypogynous 



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