THE CARPEL 245 



impossible, and interpretations of basic flower structure in syncarpous 

 ovaries have differed widely. Some flowers, under one interpretation, 

 have a receptacle prolonged beyond the distal carpels; under another 

 interpretation, there is no receptacle beyond the carpels. But the ap- 

 proximate limits of receptacle and carpel are usually evident from the 

 position of the ventral carpellary traces. Usually, the receptacle does 

 not play a prominent part in the structure of the syncarpous ovary, 

 though, under some interpretations, it has been considered to do so, as 

 in the determination of the morphology of the inferior ovary. 



The history of the receptacle in the evolution of the flower is that of 

 shortening and elimination of internodes. But, in many taxa, especially 

 in the more primitive families, a vestigial receptacle tip projects be- 

 yond the bases of the distal carpels. Here, the tip forms a definite but 

 commonly obscurely limited part of the syncarpous ovary— superior or 

 inferior. United ventral margins of the carpels have been interpreted 

 as a prolonged receptacle tip and their vascular bundles as bundles of 

 the receptacular stele. Critical comparative study of related taxa and 

 an acquaintance with the vascular supply of floral organs and the deri- 

 vation and course of their traces are necessary for the interpretation of 

 vestigial receptacle tips. 



The Inferior Ovary* 



The morphology of the inferior ovary has doubtless been discussed 

 more extensively than that of any other part of the plant body. Two 

 theories of the nature of this ovary have received strong support since 

 the early nineteenth century — the appendicular and the axial theories. 



Under the appendicular theory— also called the CandoUean and the 

 concrescence theory — the inferior ovary is considered formed by the 

 adnation of the bases of the outer floral whorls to the gynoecium; the 

 axis forms no part of the ovary waff. Linnaeus, Goethe, de Candolle, 

 Van Tieghem, Warming, and many other early botanists so interpreted 

 the inferior ovary. 



Under the axial theory— also called the receptacular theory— the in- 

 ferior ovary is considered to consist largely of tissues of the axis, to 

 represent an invaginated floral receptacle, which surrounds the 

 gynoecium. Originally the theory of the German school of botanists, it 

 was supported by Schleiden, Magnus, Payer, Eichler, Sachs, and many 

 others. 



Both theories, in essentials, go far back in the history of taxonomy 

 and morphology, with great variety in interpretation. The axial theory 

 was dominant in the later part of the nineteenth century and the first 



Daniels 



The anatomy of the inferior ovary is discussed in detail in Eames and Mac- 

 iels: "Introduction to Plant Anatomy," 2d ed., New York, 1947. 



