SUCCULENT OR FLESHY FRUITS 99 



The pyxis or pyxidmm is a form of capsule in which the 

 dehiscence is transverse, the upper part of the carpels falling 

 oiF in the form of a cap or lid (Fig. 45). Examples are seen 

 in plantain, pimpernel, and red clover. 



IV. Succulent or Fleshy Fruits. 



In these the pericarp is more or less soft and sappy and, when 

 ripe, is usually of considerable thickness. The commonest forms 

 are mentioned below. 



(i) The drupe is an indehiscent superior fruit of this class, 

 consisting of a single carpel, and usually 

 with one or two seeds. In the ripe peri- 

 carp three layers are visible, namely, (i) an 

 outer thin delicate skin, the exocarp or 

 epicarp, (2) a soft, thick, fleshy middle layer, 

 the mesocarp, and (3) a hard, bony layer, ^"^ ^ 

 the endocarp, which forms the so-called '^'°- 45- — Pyxidium of 



■* ' greater plantain {Plantago 



' stone' of the fruit. The seed of course is '""■'''"■ l.); « closed; b 



upper part removed and 



quite separate from the ' stone,' but enclosed showing the .seeds within, 

 within it (Fig. 1 24). The fruits of the plum, cherry, apricot, peach 

 and almond are drupes. The individual separate caipels in 

 a single raspberry flower become small drupes or drupels, so 

 that the whole fruit is a compound one consisting of a collection 

 of drupels. The fruit of the walnut is a form of drupe differing 

 only from those above mentioned in being the product of a 

 syncarpous gynsecium : the endocarp develops partitions which 

 extend irregularly into the fleshy lobes of the single seed. 



(ii) The berry is an indehiscent succulent fruit in which both 

 the mesocarp and endocarp are soft and fleshy. Sometimes 

 the berry is the product of superior ovary as in the grape, 

 tomato, and potato 'apple,' while in other instances it is inferior 

 as in the gooseberry (Fig. 46), cufrant, and cucumber. 



' Dates' are berries the ^stoiTe' of which is a true seed not to 

 be confused with the 'stone' of a drupe.. 



