150 VEGETABLE ORGANOGRAPHY. 



divisions observed in fruits are easily understood to 

 result from the union of the carpels. 



When the carpels are verticillate, their approaching a 

 central axis (which is called the Columella when it is 

 real, and the Axis properly so called, if it be ideal,) 

 causes them to take a triangular form; their union 

 takes place by the two sides sloping inwards, and the 

 dorsal face of all the carpels forms the external part of 

 the fruit, which results from their union. When this 

 dorsal face is uniformly convex, the fruit is round, as in 

 Rhizophora ; elliptical, as in the Coffee ; or globular as 

 in the Grape, the Elder, &c. When the dorsal face is 

 more convex than the fruit taken collectively, the fruit 

 then presents as many furrows as there are sutures, or 

 points of union of the carpels, and as many round pro- 

 jecting sides as there are convex carpels, as for example, 

 in the Melon, Ricinus, &c. If the back of the carpel 

 be angular, or if the carpel be, as it were, folded upon 

 the middle nerve, the fruit then presents as many angular 

 sides as there are carpels ; the retreating angles indicate 

 the sutures, and the projecting ones the backs of the 

 carpels, as in Hibiscus esculenlus, Oxalis, &c. ; these 

 projecting angles are sometimes even prolonged into 

 wings, as in Dodoncea. Thus all the lateral depressions 

 or eminences which are observed on the surfaces of 

 fruits, are also easily understood in the theory of the 

 union of the carpels, and depend upon their elementary 

 forms. These forms are sometimes obscured by the 

 unusual development of the fleshy part of the mesocarp. 



The most usual structure of the carpels is when their 

 two retreating faces reach into the interior of the fruit, 

 as far as the axis, and then the fruit presents as many 

 Cells (loculi) as there are carpels entering into its 

 formation ; we then say that it is Multilocular, or 

 Bi-, Tri-, Quadri-, Quinque- &c. locular, when we 



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