physiologically consider ed. 531 



Fruchthlille). The form of the fruit in Polygoneae, Chenopodese, 

 and Pkimbagineae, is exactl}' the same; the ovula are sometimes 

 longer and sometimes shorter stalked (having an umbilicus). 

 These are, comparatively, the few examples in which the fruit- 

 axis bears a single ovulum on its point; while, in all other 

 cases, they spring out of the side of it, and appear either at the 

 inner base of the seed or fruit-leaves (Fruchtblatter), or from the 

 bundle of fibres of the medullary envelope lengthened beyond the 

 point of insertion of these leaves. 



The first form shows, again, the greatest analogy to the bud. 

 The fruit-axis rises hemispherically, spindle, or conically-shaped, 

 over the flower, and is surrounded, as a covering, with several 

 rows of fruit-leaves (carpophylla), similar to the bud-leaves. At 

 the base of each of these, the rudiment of the bud, seated on 

 the axis, is metamophosed into an ovulum, and becomes enclosed 

 in the fruit-leaf, which has a tendency to turn in at the edges, so 

 that the point of insertion must always be in the edges of it, which 

 have grown together. Whether this takes place in the base or 

 top of the single seed, is determined by the length of the umbi- 

 licus. From this manner of fructification, it appears that all 

 fruits (carpidia) produced in several circles on a fruit-axis can 

 only be one-seeded, as we find in many families of i?anunculaceae 

 and Dryadeje, -such as in Ranunculus, Myosurus, Anemone, 

 Adonis, Magnol/a, Potentilla, Geum, &c. In a similar manner, 

 but only in a whorl, and at the base of a common stalk, the 

 seed-vessels of the Labiatas and ^oragineae are formed. 



The second form, where, in general, many ovula are pro- 

 duced from the bundle of fibres of the medullary envelope 

 (Markscheide) rising above the point of insertion of the fruit- 

 leaves, includes the greater part of fructification ; and we will 

 proceed from those formations that have a visible fruit-axis to 

 those in which it seems to disappear by degrees. 



1. The fruit-axis rises like a pillar, the bundle of vessels 

 forming the medullary tubes (trophospermia) ascends to its 

 summit, and developes lengthwise many ovula, which seldom are 

 diminished to one. Two of these bundles of vessels always lie 

 close together, and form a central column (placenta), which, on 

 that account, has generally two rows of teeth. 



To each of these columns there is a corresponding leaf of those 

 situated at the base of the fruit-axis in a whorl, and which here, as 

 in the bud, only serve as a protection and covering to the axillary 

 growth. In this form there are two principal modifications. 



a. The edges of the fruit-leaves bend inwards, and their cor- 

 responding bundle of fibres grows into them ; so that each pla- 

 centa, with its fruit-leaf, forms a little fruit, or seed vessel, for 

 itself. In the Malvaceae and Geraniaceae, where the fruit-axis 

 rises above the fruit, is found the type of this manner of 



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