=Dialysis of the margins of individual foliar organs.=--In cases where the leaf or leaf-like organ is ordinarily tubular or horn-like in form, owing to the cohesion of its edges, it may happen either from lack of union or from actual separation of the previously united edges, that the tubular shape is replaced by the ordinary flattened expansion. Thus, in _Eranthis hyemalis_, wherein the petals (nectaries) are tubular and the sepals flat, I have met with numerous instances of transition from the one form to the other, as shown in fig. 9, p. 24. It is, however, in the carpels that this separation occurs most frequently. When these organs appear under the guise of leaves, as they often do, their margins are disunited, so that the carpel becomes flat or open. This happens in the strawberry (_Fragaria_), the columbine (_Aquilegia_), in _Trifolium repens_, _Ranunculus Ficaria_, &c.[76] =Dialysis of the parts of the same whorl:--calyx.=--The separation of an ordinarily coherent series into its constituent parts is necessarily of more common occurrence than the foregoing. As here understood, it is the precise converse of cohesion, and it may be represented diagrammatically by a dotted line above the letters denoting the sepals, petals, &c. When this change happens in the calyx we have the gamosepalous condition replaced by the polysepalous one, as thus represented: ............. S S S S S instead of _____________ S S S S S as in a calyx of five coherent sepals. Detachment of this kind occurs not unfrequently, as in _Primula vulgaris_, _Trifolium repens_, &c. In _Rosaceae_ and _Pomaceae_ this separation of the calyx is of the more moment, as it has reference to the structure of the inferior ovary, as will be more fully mentioned hereafter. Here, however, a case recorded by M. J. E. Planchon may be alluded to[77] wherein a quince fruit (_Cydonia_) was surmounted by five leaves, the surface of the pome being marked by as many prominences, which apparently corresponded to the five stalks of the calycine leaves. In this specimen, then, the inferior position of the ovary appeared to be not so much due to an expansion of the fruit stalk, as to the fusion of the hypertrophied stalks of the sepals. Some of the malformations among Cucurbits point to a similar structure. It is probable that in many of these cases the so-called inferior ovary is partly axial partly foliar, _i.e._, sepaline, and partly carpellary in its nature. Dialysis of the sepals in calyces that are usually gamosepalous has been most frequently observed in _Rosaceae_, _Pomaceae_, _Umbelliferae_, less commonly in _Leguminosae_, also in the following genera:--_Primula_, _Symphytum_, _Gentiana_, _Campanula_, &c. [Illustration: FIG. 30.--Dialysis of the sepals and petals in _Correa_.]