384 ON CHORISIS. 



other Caryophyllaceous plants. This is more like a case of real «?/- 

 douhlement or unlining, a partial separation of an inner lamella from 

 the outer, and perhaps may be so viewed." But the close relation of 

 the petal to the stamen, and the many instances of a condition inter- 

 mediate between the two are well known, and it seems easy and natu- 

 ral enough to regard the crown as an imperfect development of anthers 

 whilst the expansion above it corresponds with the petal-like enlarge- 

 ment of the connective in some stamens, and the claw with the fila- 

 ment. Here then, we need no new principle, and find no real exception 

 to recognised laws. The appendage to the stamen in Larrea and other 

 Zygophyllaceae is perhaps as good a case as can be found for the ap- 

 plication of the stipule theory which has here not a little plausibility, 

 although when we consider the modifications of development in a 

 single petaloid organ as shown in Eanunculus with its petal scales, 

 Helleborus with its nectariferous cup ; some species of Lilium with their 

 protrusions on the surface, and again the cases among the grasses of 

 awns which are the midribs of the glumes or palese to which they be- 

 long, departing at some distance below the apex, we, perhaps, ought 

 not to consider the appearances as inconsistent with the supposition of 

 one organ developed in an unusual manner. Perhaps the appendages 

 at the base of the anther in Erica are quite as strange as if they occur- 

 red at the base of the filament, and the stamen growing from the ex- 

 tremity of a petaloid process in Campanula not much less anomalous 

 than if it rose from the same lower down, or at the base. Then we 

 have the stamen of Asclepias with its extraordinary appendages which 

 is as like the unlining of an organ as anything we are acquainted with, 

 yet undoubtedly is no more than a mode of development of the one 

 modified leaf. 



The next example is taken from the genus Parnassia with its curious 

 and beautiful appendages [nectaries of Linnaeus] opposite to the petals 

 immediately within them, and thence inferred to be derived from them, 

 or, as it were, a part of the same organ. These appendages may be 

 some justification of collateral chorisis though the multiplication of 

 parts is incomplete, but I confess I can find no reason for denying 

 them to be a circle of parts originating distinctly in the torus, although 

 they are placed opposite to the exterior circle. I have given reasons for 

 believing that oppositeness alone is no argument for identity of origin in 

 organs, and if it were, the fertile circle of stamens in Pamassia must 

 be accounted only a transverse chorisis of the carpels, as the members 



