266 PRACTICAL COURSE IN BOTANY 
whether of one or more carpels, as the peach, cherry, bean, 
and lemon. 
302. Accessory fruits are so called because some other 
part than the seed vessel, or ovary proper, is coherent with, 
or accessory to it, in forming the fruit, as in the apple and 
the hip. The accessory part may consist of any organ, but 
is more frequently the calyx or the receptacle. In the straw- 
berry, the little hard bodies, usually called seeds, that dot 
the surface are the true fruits (akenes). A vertical section 
through the center will show the edible part to consist 
400 401 
Fics. 400, 401.— Vertical sections showing the relation between a strawberry 
flower and fruit: 400, the flower; 401, the fruit developed from it. The corre- 
sponding parts are indicated by connecting lines; r, receptacle; a, sepal; b, petal ; 
3, stamens; ¢, carpel (akene in fruit) ; p, style of the pistil ; pl, pulp of the fruit. 
wholly of the enlarged receptacle. In the pineapple, the 
edible stalk may be traced through a mass of flowers 
whose seed vessels have become enlarged and ripened into 
fruits. 
303. Aggregate fruits. — Some accessory fruits, the straw- 
berry and blackberry for example, are, at the same time, 
aggregate ; that is, they are composed of a number of sepa- 
rate individual fruits produced from a single flower. The 
cone of the magnolia and of the tulip tree are aggregate 
fruits; can you name any others? 
